Eastnor Township was located on part of the northern portion of the Bruce Peninsula, Bruce County, Ontario.
On June 18, 1869, the township of Eastnor was united for municipal purposes to the township of Albemarle pursuant to a County by-law. Its first council was elected in 1870.
On January 1, 1873, the townships of Lindsay and St. Edmunds were added to the union (through County by-law passed on June 21, 1872) forming the municipality of the United Townships of Albemarle, Eastnor, Lindsay and St. Edmunds.
On January 1, 1878, Albemarle Township became its own municipality, by by-law dated June 8, 1877, while the three northern townships remained united, with Eastnor as the senior township.
On January 1, 1883, Lindsay and St. Edmunds were set apart as their own municipality, having attained the required qualifications within their bounds, with Eastnor Township becoming its own municipality.
Lion’s Head, which was part of the Township of Eastnor, incorporated as a village in 1917.
On January 1, 1999, St. Edmunds Township, Eastnor Township, Lindsay Township and Lion’s Head amalgamated to form the Municipality of Northern Bruce Peninsula.