Osborne told the Federation of German Industry (BDI) that he believed in a "Wertegemeinschaft" (community of shared values) between the two countries based on their "mutual respect and tolerance of difference; openness and a commitment to freedom."
A day after meeting Finance Minister Wolfgang Schäuble, Osborne praised Germany as the other half of Europe's economic powerhouse, while talking up Britain's importance to the EU's foreign policy and military strength.
But the focus of the speech was on the differences between the two countries, as he repeated the message that Brits would never accept 'ever closer union' as called for in EU treaties and demanded fairer treatment for non-Eurozone countries inside the EU.
"We in Britain can support you in the Eurozone [to] make the lasting changes that you need to see to strengthen the euro," Osborne said.
"In return, you can help us make the changes we need to safeguard the interests of those economies who are not in the Eurozone."
Keep non-euro countries on board
For Osborne, the UK needs reforms that guarantee businesses won't be penalized for using a non-euro currency, that non-Eurozone taxpayers won't be called upon to bail out euro countries, and an extension to the single market in financial services.
"These demands are known to us [Germans] and they're also in our interest," Andreas Meyer-Schwickerath, general manager of the British Chamber of Commerce in Germany told The Local.
German financial services firms which operate across Europe should also be keen to see the single market completed, he pointed out, as companies like insurance giant Allianz are keen to operate over borders.
Meanwhile, BDI business leaders will have made for a receptive audience, Meyer-Schwickerath said – although the message needed to reach a broader swathe of people in both countries.
"We know there will be a major economic impact should Britain leave the EU. This impact should be known to Germans and the British public," he urged.
Commentator for The Economist Jeremy Cliffe tweeted that it was the right speech for the BDI audience - but that it remained quite vague.
Verdict: well-calibrated pitch to moderately interested audience. But "new detail" we were promised rather limited.— Jeremy Cliffe (@JeremyCliffe) November 3, 2015
Prime Minister David Cameron is expected to publish an open letter to EU Council President Donald Tusk later this week detailing Britain's aims for EU reform, which he has so far kept close to his chest.
Help 'wherever we can'
Osborne's speech chimed with Chancellor Angela Merkel's earlier appearance, when she repeated her determination that "the UK should remain an EU member" and pledged German help "wherever we can" to prevent 'Brexit' from the EU.
But the British people would have to decide for themselves at the ballot box, Merkel acknowledged.
Cameron has promised a referendum before the end of 2017 on whether the UK should leave the EU.
In the meantime, he has been buttering up European leaders, especially Merkel and her ministers, in a bid to secure reforms that will address concerns among his Eurosceptic MPs and the wider public.