At the outset the war wasn’t against Britain Rather, it was generally understood from within the German government and mainstream national opinion to be one of defence against the danger from the Russian nation moving in support of its formal Orthodox ally Serbia and therefore reinforcing a ‘Slavic’ threat to the Austrian Empire – and with it to Germany itself, along its 1000 miles of shared border. The might of the Russian army increasing by an annual recruitment programme of 500,000 men taking its strength to 2 million was alarming for Germans given its own army was a third of that (much more secure against that of the UK: 150,000). And Russia had renewed links with both France and Britain. Cumulatively, the sense of alarm at being surrounded was real. This was understood as justification for a ‘defensive attack’.
They were not immune to co-ordinated propaganda from the War Office to the effect that world-leading German culture and values would be destroyed The German people had good reason to be proud of the country’s intellectual and artistic achievements. These were internationally acclaimed. There had been warnings, as from Nietzsche, that not to boast this strength was self-destructive. The message from evolutionary biology was that nationally they were at the cutting edge of social and political fitness for human survival and development. There had been adult male voting rights since 1871 (not till 1918 in the UK).
Establishment Christianity reinforced the general sense of national loyalty and patriotic trust in the government Biblical teaching and subsequent church tradition encouraged the theocentric belief that those in positions of political authority would not hold such posts unless the will of God was underwriting their appointment in the first place. If national leaders were clear that the war efforts were just, that settled it. There was every reason to trust in the zeal of God to bring the history of salvation to fruition via the power struggles of the nation. The position of the Kaiser was there by divine right as was his authority and responsibility for maintaining the interests of the nation . https://www.academia.edu/36688515/State_War_Revolution_and_the_German_Evangelical_Church_1914_18.
Intrinsic difference between British and German theologies of statehood This is argued by the Australian historian John A Moses ‘The Theological Component of World Conflict: The Example of the Anglo-German Antagonism 1914–18’. St Mark’s Review 209:3 (2009) pp 39-58.
file:///C:/Users/NewUser/Downloads/The_Theological_Component_of_World_Confl.pdf
Formal endorsement by Kaiser as Head of Lutheran State Church
"Remember that the German people are the chosen of God. On me, on me as German Emperor, the Spirit of God has descended. I am His weapon, His sword and His vizard. Woe to the disobedient ! Death to cowards and unbelievers ! " Quoted against him in a speech by PM Lloyd George  http://www.archive.org/stream/honourdishonours00lloy/honourdishonours00lloy_djvu.txt
The rationale was elaborated in speeches drafted for him by Adolph von Harnack (General Director of the Royal Library at Berlin and internationally renowned for his studies of the history of early Christianity and what constituted its essence.) The first was given on August 4^th to the Diet of the German Empire, assembled in the Reichstag building setting out the moral case for war, and the second – a Call to the German People - on August 6th. Background: Rowan Williams The Deadly Simplicities of Adolf von Harnack – Liberal Theology in Germany on the Eve of the Great War https://lif.blob.core.windows.net/lif/docs/default-source/default-library/rowan-williams---the-deadly-simplicities-of-adolf-von-harnack---january-2014---lecture-transcript-pdf.pdf?sfvrsn=0; https://www.counter-currents.com/2017/02/adolf-von-harnacks-dark-theology. 
Wolfram Kinzig ‘Harnack Houston Stewart Chamberlain, and the First World War’ 
https://www.academia.edu/40878174/Harnack_Houston_Stewart_Chamberlain_and_the_First_World_War 
A Second Pentecost (from a sermon by Gustav Freybe in Hanover on Whit Sunday 1915)
"When the day of mobilization had fully come, there were Germans all together in unity - villagers and city dwellers, conservatives and freethinkers, Social Democrats and Alsatians, Welfs and Poles, Protestants and Catholics. Then suddenly there occurred a rushing from heaven. Like a powerful wind it swept away all party strife and fraternal bickering... The apostles of the Reich stood together united on the fourth of August, and the Kaiser gave this unanimity the most appropriate expression: 'I see no more parties, I see only Germans!" Quoted by A J Hoover God, Germany and Britain in the Great War (1989) p 11. This sense of intimate bond between Holy Geist and German geist was pervasive and strong.
Manifesto of the Ninety-Three Two months after the start of WW1 leading academics from across German universities and their academic disciplines protested vigorously against what they saw as false misrepresentation of Germany engagement with the war.  It begins: "It is not true that Germany is guilty of having caused this war. Neither the people, the Government, nor the Kaiser wanted war. Germany did her utmost to prevent it; for this assertion the world has documental proof." It denies any disregard for Belgian citizens, their property, and the city of Louvain, or for international law. And it concludes: "Were it not for German militarism, German civilization would long since have been extirpated. For its protection it arose in a land which for centuries had been plagued by bands of robbers as no other land had been. The German Army and the German people are one and today this consciousness fraternizes 70,000,000 Germans, all ranks, positions, and parties being one. We cannot wrest the poisonous weapon - the lie - out of the hands of our enemies. All we can do is to proclaim to all the world that our enemies are giving false witness against us. You, who know us, who with us have protected the most holy possessions of man, we call to you: Have faith in us! Believe, that we shall carry on this war to the end as a civilized nation, to whom the legacy of a Goethe, a Beethoven, and a Kant is just as sacred as its own hearths and homes.  For this we pledge you our names and our honour." 
Those signing included were internationally renowned in archaeology, architecture, astronomy, biology, chemistry, classics, drama, economics, history, law, linguistics, literature, mathematics, medicine, music, painting, philology, philosophy, physics, poetry, sculpture, statistics. Fourteen were Nobel Prize winners. Amongst them there were also ten theologians, including ones frequently cited in British scholarship: in addition to Adolf von Harnack, Adolf Deissmann, Wilhelm Herrmann, and Reinhold Seeberg.  
https://delong.typepad.com/sdj/2014/10/liveblogging-world-war-i-october-4-1914-manifesto-of-the-ninety-three.html.
Comment on the Manifesto It is difficult not to consider the fact that university professorships were all state appointments might well have created a built-in disposition to serve the political masters. In retrospect their judgement, however genuinely believed, is exposed as deeply mistaken: A Kramer and J Horne German atrocities, 1914: a history of denial.
Ongoing endorsement of the war from pulpits and church sponsored publications From the start, the supporting message was clear. Germany was David to Britain's Goliath and jealous Cain:
Ernst von Dryander (in effect Imperial chaplain and Wilhelm’s family friend). On August 4^th 1914 he preached at the official state service using the text If God is on our side who can be against us? Romans 8:3 and giving the following reassurance: ‘We are going into battle for our culture against the uncultured, for German civilization against barbarism, for the free German personality bound to God against the instincts of the undisciplined masses. And God will be with our just weapons! For German faith and German piety are ultimately bound up with German faith and civilization.’ The nation under God must be protected against ‘three bloodthirsty hyenas’.
Paul Klein in Mannheim: God’s help is assured because the German people, in spite of any failings of their own, are still the most Christian in contrast to Russia’s superstition, France’s frivolity and England’s hypocritical Pharisaism. https://christuskirche-karlsruhe.de/files/pdf/2014-Mit%20Gott%20fuer%20Kaiser%20und%20Vaterland%20-%20Vortrag.pdf.
Otto Dibelius (pastor and subsequently Bishop during and after WW2) announced ‘Never has the German people gone to war for a more sacred cause’. This theme is reflected in each of the several collections of war sermons: God with us! (1914), God's call in Germany's fateful hour (1915), The kingdom of heaven is near! (1915) The harvest of the faith (1916), Through to freedom! (1917), He is well on our plan (1917) and We German Christians and German Peace (1918). http://www.ossietzky.net/5-2014&textfile=2579;https://archive.org/stream/strangecaseofbis00dibe/strangecaseofbis00dibe_djvu.txt.
Eduard Le Seur (pastor in Berlin-Lichterfelde) New Year’s Day 1915 sermon ‘Our distant descendants will sing and say of this year the most terrible struggle of nations on earth, of the half-world invasion of peaceful Germany, of German unity and sacrifice, of German strength and heroism, of never-before-seen victories of German arms, and of tough, moving struggles in the East and West, at sea and in the skies. - Blood red is the radiant wreath in whose jewelry the year 1914 has sunk into the sea of ​​times; but it is a radiance that will show the way to German greatness for all generations to come.’ http://www.pfarrerverband.de/pfarrerblatt/index.php?a=show&id=3653. 
A perversion of the Lord's Prayer by Pastor Dietrich Vorwerk in his 1917 collection of poems
"Though the warrior's bread be scanty, do Thou work daily death and woe unto the enemy.
  Forgive in merciful long-suffering each bullet and each blow which misses its mark!
  Lead us not into the temptation of letting our wrath be too tame in carrying out Thy divine judgement!
  Deliver us and our Ally from the infernal Enemy and his servants on earth.
  Thine is the kingdom, the German land;
  May we, by aid of Thy steel-clad hand, achieve the power and the glory."
translated in J P Bang Hurrah and Hallelujah: The Spirit of a New-Germanism, a Documentation (2014) p 42.
Parallel support for the war from the RC Church in Germany
https://www.evangelische-aspekte.de/kriegspredigten-im-ersten-weltkrieg
The stance of German Catholics is best represented by Michael von Faulhaber who is quoted as preaching that that the war was a textbook example of a just war. As Bishop of Speyer and subsequently of Munich he was in effect responsible for military chaplaincy, being awarded the Iron Cross in 1916 for his presence with the troops on the Western Front. With fellow bishops he exhorted the faithful not to give up hope: the church was no less concerned to protect the throne as it was the altar - against internal and external enemies. (Patrick J. Houlihan Catholicism and the Great War: Religion and Everyday Life in Germany and Austria-Hungary, 1914 -1922, p 53.)       

Catholic Cardinal Bettinger visiting the German Western Front in 1916                                       https://commons.wikimedia.org/wiki/File:Kardinal_Bettinger_Krieg_1916JS.jpg 
Engelbert Krebs - an influential  Catholic theologian preached  a 'war theology' but qualified it by reference to the Gospel commandment 'to love our enemies' "We must be ready to die for something higher than the individual, for the Fatherland, for our German way of life and customs. Those who praised an individual’s “living life to the fullest” as the highest goal were shown to be wrong. The seed must die to bring forth fruit – this lesson was once again acknowledged by everyone. And had it not been acknowledged, Germany would be destroyed today....To be sure, with an iron fist our army is turning back our enemies from the borders that they wickedly attacked. And the army is doing the right thing. But the hatred that many wish to foment in us at this time—we must not allow it to prevail, even if doing so requires sacrifices of us. In the depths of our hearts we must also love our enemies, and we must “pray for those who persecute us.” (Matthew 5, 44) http://ghdi.ghi-dc.org/sub_document.cfm?document_id=950
Matthias Erzberger - leader of the Catholic Centre Party - formally proposed the 1917 Reichstag Peace Resolution' which qualified the position hitherto supported by the Church in Germany. https://ghdi.ghi-dc.org/sub_document.cfm?document_id=987

Ecumenical hymn-singing in front of the Reichstag When war was declared thousands of Protestants and Catholics joined together in an open-air interdenominational church service singing each others' hymns. The mood was upbeat and enthusiastic, confident in both faith and culture (Captured in Modris Eksteins' Rites of spring. The Great War and the Birth of the Modern Age 1989). It was reflected in the common sentiment:Let’s sing on the way to war. This was the theme of Richard Dehmel Feldsoldat marching song with its resounding                                 As all this rests in God’s hand
                              We’re glad to march for the father land.
https://gutenberg.spiegel.de/buch/auswahl-deutscher-gedichte-fur-hohere-schulen-4504/597.
Happy Easter postcards

http://embed.europeana1914-1918.eu/en/contributions/15521#prettyPhoto[gallery]/0/ 
https://www.reddit.com/user/xxSurveyorTurtlexx
Easter eggs and bunnies were common on both postcards and stamps. 
The play Des lieben Gottes kleine Soldaten - God's Little Soldiers written by a nun in 1916 has children going off to fight by dropping bombs on Belgium (George L Mosse Fallen Soldiers. Reshaping the memory f the world wars (1990) p 143.
An overview Dr. Jörn Halbe Patriotism, Desire for war and Christian faith: The Churches of the German Reich in the First World War
https://www.denk-mal-gegen-krieg.de/assets/Texte/3-Geschichte/Jorn-Halbe-uber-die-Kirchen-im-1.Weltkrieg.pdf.