Mrrzy, the link keberoxu gave on 12 Aug 19 - 03:12 PM, while not absolutely accurate, answers your question correctly. "Ick" is the imaginary pronunciation by a Frenchman of the Standard German word "ich".

The lyrics have no reference to Alsace at all, according to the various commentators. However, the song has been collected in Alsace towards the end of 19th century, where and when it seems to have acquired some new significance, unintended by the original author. The above commentator, a native Alsatian, also has a specific (biased) view on the topic, based on the idea of a separate Alsatian identity.

Also, people write that the core of the lyrics predates Napoleon, and that some verses were added later. Nevertheless, the gist remains unchanged. The main point being mildly ridiculed is that the cliché Frenchman will always talk about l'amour, even if disabled and possibly addressing ladies of advanced age.