Aylmer is a town in Elgin County in southern Ontario, Canada, just north of Lake Erie, on Catfish Creek. It is 20 kilometres (12 mi) south of Highway 401. Aylmer is surrounded by Malahide Township.

In October 1817, John Van Patter, an emigrant from New York State, obtained 80 ha of land and became the first settler on the site of Aylmer. During the 1830s a general store was opened and village lots sold. Originally called Troy, in 1835 it was renamed Aylmer after Lord Aylmer, then Governor-in-Chief of British North America. By 1851 local enterprises included sawmills and flour-mills powered by water from Catfish Creek. Aided by easy access to Lake Erie, Aylmer became by the mid-1860s the marketing centre for a rich agricultural and timber producing area. Benefiting greatly from the construction of the 230 km Canada Air Line Railway from Glencoe to Fort Erie, Aylmer became an incorporated village in 1872.

A Royal Canadian Air Force Training Facility, RCAF Station Aylmer was located just north of Aylmer in Malahide Township from 1941 to 1961.This station is now home to the Ontario Police College and The Aylmer Wildlife Management Area. The College Is situated on 121.5 hectares of rural land five kilometers northeast of the town of Aylmer, Ontario (190 km west of Toronto). The college has 165 full and part-time employees including instructors, support and seconded staff. The 45 permanent instructors are supplemented by police officers from various police services, usually for two-year periods. With very rare exceptions, all Police Officers in Ontario, Canada attend the college for their 15-week program in order to receive their Basic Constables diploma. Once they have received the Diploma and after they have been sworn in as Peace Officers, they can then work in the Province of Ontario as police officers.

In the mid-1970s, many German-speaking Mennonites began migrating to the Aylmer area from Mexico. The Mennonites were Canadian citizens who had moved to Mexico from Manitoba and Saskatchewan during the first half of the 20th century. By the early 21st century, there was a large Mennonite population in Aylmer and the surrounding area. In addition to the Mennonite population there are sizable Dutch, German, and British descended populations in the area.

Just east of Aylmer is a sizable Old Order Amish community. This community was founded by families moving from Ohio in 1953. They were uncomfortable with a nuclear facility being constructed close to their community in Ohio. Since that time, the community has grown to encompass three "districts" the surrounding area. A number of members from this community participate in the weekly Aylmer Sales Barn and sell fruit, vegetables, eggs, and animals, such as rabbits and chickens. This particular Amish community eschews the use of automobiles, electricity, and most modern conveniences. A well-known Amish publishing house, Pathway Publishers, is based in this community.

The tobacco growing industry played a large part in the economic development of Aylmer. Imperial Tobacco Canada built a plant in Aylmer in the mid-1940s. At its peak, Imperial employed more than 800 full-time and seasonal workers.

en.wikipedia.org/wiki/Aylmer,_Ontario