Claim: Adolf Hitler became the chairman of the NSDAP in 1921.
Evidence: He joined the German Workers ' Party -LRB- DAP -RRB- , the precursor of the NSDAP , in 1919 and became leader of the NSDAP in 1921.
The chairman -LRB- also chairperson , chairwoman or chair -RRB- is the highest officer of an organized group such as a board , a committee , or a deliberative assembly.