Prior to the 2023 governance reform, for governance purposes it was comprised a single local service district and parts of one town and one village, all of which were members of the Western Valley Regional Service Commission (WVRSC).

[5] The parish extended west to include part of Maine claimed by New Brunswick.

In 1842 New Brunswick's land boundary with Maine was settled by the Webster–Ashburton Treaty, ending Wicklow's implicit claim to part of the state.

In 1850 the boundary within the Saint John River was altered, adding any islands in front of the parish to Wicklow.

In 1870 the boundary with Simonds and Wilmot Parishes was moved south to start at its original point at the mouth of the Whitemarsh but then run westerly along the prolongation of the northern line of southernmost lot of the grant to Henry M.