Complex sentence: Some were established after 1800 on the frontier, such as the First African Baptist Church of Lexington, Kentucky, which by 1850 had 1,820 members, the largest of any Baptist church in the state.
Split into simpler sentences: Some were established after 1800 on the frontier, such as the First African Baptist Church of Lexington, Kentucky. By 1850 First African had 1,820 members, the largest of any Baptist church in the state.