Silas Hemenway Jennison was an American Anti-Masonic and Whig politician who served as Vermont's 11th lieutenant governor and 14th governor of Vermont – the first born in the state.

The Anti-Masonic Party was the earliest third party in the United States. Formally a single-issue party, it strongly opposed Freemasonry in the United States. It was active from the late 1820s, especially in the Northeast, and later attempted to become a major party by expanding its platform to take positions on other issues. It declined quickly after 1832 as most members joined the new Whig Party; it disappeared after 1838.