Cedar Creek Township was uninhabited from the time the Indians left in 1817 until 1833 when Mr. Wood from New York built a cabin on the bank of Cedar Creek. Mr. Wood left the wilderness home after one year and was followed to the Cedar Creek area by Jacob Notestine and John Manning, along with their families, who planted the first corn in the area in 1834. Later, in 1836, Mr. Notestine planted the first orchard with trees that he purchased from John Chapman, who was more popularly known as "Johny Appleseed."

In 1835 a state road called the Fort Wayne and St. Joseph was the first road surveyed in Cedar Creek Township. It was a continuation of an existing road that connected the area with Fort Wayne.

The first religious meeting was held in 1836 by Rev. Hickland, of the Methodist Protestant Church in Jacob Notestine's house. The first store was opened in 1838 by Thomas Hamilton in the village of Hamilton, which was later referred to as the village of Leo. The first post office was located in Hamilton in 1847. It was called the Leo Post Office.

In 1837 the first schoolhouse was built near the center of Cedar Creek Township. The site was in a wet, inaccessible area, where few children were located. Because of the schoolhouse's remote location, it was never used for its intended purpose. In fact, the first election in the area was held in this building in 1837 and no more than half of the township population could find it to vote. The building was left to decay.

Little information can be found to describe Cedarville and its relatively slower development. Cedarville was actually platted approximately ten years earlier than Hamilton (Leo). Cedarville was laid-out in May 1838 and Hamilton (Leo) was laid out in February 1849.

In 1956 the Cedarville dam was constructed and the Cedarville Reservoir began to form, retaining 500 million gallons of water. A backup reservoir, named Hurshtown was constructed 13 years later which holds 1.7 billion gallons of water.

The population of the Leo-Cedarville area remained small from the time of the first settlement in the early 19th century into the late 20th century. During the 1990s, however, the number of people in Leo Cedarville began to increase rapidly. From 1990 to 1997 the population increased from 1,818 to 2,391; an increase of almost 32% in only 7 years. This rapid growth and the threat of annexation from the neighboring city of Fort Wayne prompted citizens of the Leo-Cedarville area to incorporate into a town on January 1, 1996.

Sources (including: www.leocedarville.com):

Brant and Fuller. Valley of the Upper Maumee, Vol. 1. Democrat Printing Co., Madison: 1889
City of Fort Wayne Water Engineering Department and Water Filtration Department. June 1997
Helm, T.B. History of Allen County, Indiana.
Kingman Brothers, Chicago: 1880
Tanner, Helen Hornbeck. Atlas of G. L. Indian History University of Oklahoma Press: 1987