Page "Politics of Germany" Paragraph 26

The duties of the Bundespräsident ( Federal President ) are largely representative and ceremonial.

He is not a member of the government.

The President is elected every five years by the Federal Assembly ( Bundesversammlung ), a special body convened only for this purpose, comprising the entire Bundestag and an equal number of state delegates selected especially for this purpose in proportion to election results for the state diets.

Most Presidents have been members of the CDU as this party is usually the strongest in the Bundestag and also often in the states.