In 1856, the Republican Party met for the first time to put together a platform
http://alpha.furman.edu/~benso…
and ready itself for the first presidential run. Chicago was chosen for the first convention. The convention was held at the Wigwam,
a wooden structure built expressly for the convention. The Republican Party appointed delegates at the state level. These people were chosen to determine the best candidate to represent the party in the general election.
Cross posted at EENR