Westfield was founded on May 6, 1834, by North Carolina Quakers Asa Bales, Ambrose Osborne, and Simon Moon.

[7] It is believed that the town was planned as a stop on the Underground Railroad with many families of the Religious Society of Friends and the Wesleyan Methodist Church supporting the cause.

[8] On January 1, 2008, Westfield was incorporated as a city, and Andy Cook was sworn in as mayor.

[11] In 2014, the city opened Grand Park Sports Complex which hosted the 2016 Big Ten Conference Men's Soccer Tournament.

An indoor events center opened in July 2016 that features three full-size multipurpose fields, and an indoor basketball/volleyball facility that features eight courts, with two of them being NBA-regulated, also opened and is named after the NBA's Indiana Pacers.

Grand Park features an abundance of green space and more than 10 miles (16 km) of pedestrian/bicycle trails, including the largest trailhead on the Monon Corridor.

Since opening, the campus has hosted several major events including: Whale of a Sale Consignment Event, Little League Softball and Baseball Region Tournaments, USA Archery Finals, Big Ten Women's and Men's Soccer Tournaments, US Club Soccer NPL Finals and Nationals, Suburban Indy Consumer Shows, plus many more.

In 2017 Westfield signed a 10-year contract with the NFL's Indianapolis Colts for their annual training camp.

[21] Westfield hosts the Great Lakes Regional Tournament in the Little League World Series each year.

Westfield also has a contract with the NFL's Indianapolis Colts to host their yearly training Camp at the Grand Park Sports Campus.