Born out of an Illinois prairie frontier, this community known as McHenry first took shape as hunting and fishing grounds of the Potawatomie Indians.
In 1836 McHenry County was created out of Cook County and included present day Lake County. Both the county and the city were named after Major William McHenry who served in the war of 1812 and the Blackhawk War. McHenry served as the first seat of government until 1844 when Lake County was established on its own.
In the early days McHenry's center of commerce had three divisions with a strong rivalry existing among them. The Riverside section (Riverside Drive) was the first to be established along the Fox River. The West McHenry area (Main Street) was named Gagetown for George Gage who owned the site and was influential in securing the Northwest Railroad (Metra) in 1854. The Green Street area, was once called Centervillle.
During the first half of the 19th century, McHenry flourished as a resort area because of the Fox River, surrounding lakes and easy accessibility from Chicago. For decades, McHenry took very seriously its title as the "Gateway to the Chain-of-Lakes".
In spite of its beauty and strong attraction to tourists, McHenry owed her growth to the stability provided by the many farmers who worked the fertile land as well as new factories such as Admiral, Borden and The Hunter Boat Co. arriving on the scene and industries such as lumber, cigars, clay, food products and brewing that helped draw new residents to the area. The drainage of a large 60 acre pond that previously divided the community in half, contributed to increased development and improved roadways while the railroad allowed commuters to find this area the perfect place to settle with their families.