You have lived in the U.S. for many years and plan to move back to Germany? A new law, in effect since April 1, 2007, makes it easier for returning pensioners to get access to health insurance in Germany. Please find more information here, only available in German:

Ministry of Health

If you have worked in the U.S. and receive social security by the U.S. Social Security Administration please contact your local Social Security Office to have your payments transferred to Germany. You can find additional information here:

Webpage of the Social Security Administration