History of Deism
Deism began with Lord Herbert of Cherbury in 1648. Just over 2 centuries later Deism began to fall in popularity after the works of Charles Darwin. Darwin showed that Intelligent design isn't needed to explain life, he and others began to turn prospective Deists into Atheists and Agnostics. Despite this there is still Deism in the World and a modern definition has been created and provided by the World Union of Deists (WUD).
"Deism is the recognition of a universal creative force greater than that demonstrated by mankind, supported by personal observation of laws and designs in nature and the Universe, perpetuated and validated by the innate ability of human reason coupled with the rejection of claims made by individuals and organized religions of having received special divine revelation."
That gives a modern understanding of deism.
Deism In America
Deist's in America played a large role in the separation of church and state. Many founding fathers were Deists or influenced by Deist philosophy such as Benjamin Franklin, Thomas Paine was a large advocate of Deism, James Madison, Thomas Jefferson, John Adams and George Washington. Jefferson and Adams were what's called Christians Deists, that means they accepted the moral teachings of Jesus but didn't believe that Jesus was God. 
Conservapedia hates Deism and calls it "A slippery slope to Atheism. They often try to say that Deistic thought had little to do with the foundation of America, despite the fact that many founding fathers were Deists and the fact that Deism influenced them to have religious freedom in America. If America were a Christian nation founded on Christian values they might have made it so everyone would be forced to be Christians. It isn't and we have Deistic thought to thank for this. Deists don’t cause the type of harm that Christian fundamentalists cause in the Bible Belt.
Less nice Deists
Well.... Just like all religions (and lack of faith groups) there have been some bad Deists, such as possibly Napoleon Bonaparte. How the fuck was Napoleon bad? Well he made himself into a Dictator but was better than many other absolute rulers. Overall Deists tend to be very tolerant of others and although they are now a small movement they are now getting more attention due to much of the western world becoming more secular.