What did workers do when they signed yellow-dog contracts

A yellow dog contract is an employment contract that includes a commitment by the worker not to be a member of a labor union.  These contracts were extended in the United States until the 1930s to prevent the formation of trade unions. In 1932, yellow dog contracts were abolished in the United States by the Norris-LaGuardia Act.

disease was the number one killer of native peoples. they had had little exposure to the diseases of europe. this led to some villages being almost completely wiped out and some tribes destroyed.