Originally established around 1700 as "Blanchard's Village" by Acadian farmers, they lived here for sixty years, building dykes that are still in use. Before the Great Expulsion of the Acadians in 1755, the area was almost 100% French. Now, few Acadians live there, though there are several Acadian settlements on the opposite bank of the Petitcodiac River, such as Pre d'en Haut, New Brunswick.
On September 4, 1755, the Battle of Petitcodiac was fought near Hillsborough. After the capture of Fort Beausejour during the Seven Years' War, in an attempt to gain control over the region, the British sent a punitive expedition consisting of two companies of British colonial troops into the Petitcodiac River Valley to destroy the Acadian settlements located there. While the main body finished their operation on the eastern bank, a detachment was dispatched to the western bank. When the detachment under Major Joseph Frye approached Blanchard's Village, located near where Hillsborough now stands, it encountered French forces under the command of Captain Charles Deschamps de Boishébert and was driven off with heavy losses. The site is marked by a National Historic Sites and Monument plaque.
In 1766, a group of settlers arrived in the area led by Matthias Somers, Michael Lutz, Jacob Trietz (Trites), Charles Jones, and Heinrich Stieff (Steeves). Heinrich Steeves had seven sons and the name Steeves is still common among residents.