[19] Interlaken was authorized for prospective incorporation as a borough by an act of the New Jersey Legislature on March 11, 1922, from portions of Ocean Township, subject to approval by a majority of voters in the affected area.

[22][23] The area that is now Interlaken was purchased in 1667 by Gavin Drummond from the Lenape Native Americans.

It was later part of Ocean Township, which had seceded from Shrewsbury Township in 1849 and included at the time present-day Eatontown, Neptune Township, Neptune City, Avon-by-the-Sea, Bradley Beach, Asbury Park, Allenhurst, Deal, Long Branch, West Long Branch, Loch Arbour, Monmouth Beach, Sea Bright, and Oceanport, along with Interlaken itself.

[24] Dr. Francis Weld, a Boston physician, bought a 364-acre (1.47 km2) tract and named it Interlaken Farm, after Interlaken, a peninsula in Switzerland situated between two lakes, that they had just visited, which was similar to the borough's location between two sections of Deal Lake.

[25] Weld established the Interlaken Land Company in 1890 to turn his farm into a residential community with avenues named after English lakes and cross streets named after the islands in the Hebrides in the Irish Sea.

While the initial effort did not succeed, the Stormfelz-Lovely-Neville Company was hired in 1905 to continue the building project, and the community began its growth.

[24] Interlaken was formed as a borough on March 11, 1922, based on the results of a referendum held on May 3, 1922.

[1][2] The borough borders the Monmouth County community of Allenhurst, Asbury Park, Loch Arbour and Ocean Township.

[30] The 2010 United States census counted 820 people, 361 households, and 237 families in the borough.

[5] The borough form of government used by Interlaken is a "weak mayor / strong council" government in which council members act as the legislative body with the mayor presiding at meetings and voting only in the event of a tie.

The mayor can veto ordinances subject to an override by a two-thirds majority vote of the council.

[37][38] As of 2025[update], the mayor of Interlaken is Republican Michael Nohilly, whose term of office ends on December 31, 2027.

[39] Members of the Borough Council are Council President John Rush Butler (R, 2025), Leonard Blasucci Jr. (R, 2025), Michael Delia (R, 2024), Michael DeSarno (R, 2027), Mervin Franks (R, 2026), Daniel T. Griffin (D, 2027) and Mindy Horowitz (R, 2026).

[3][40][41][42][43] In July 2018, the borough council selected Rick Menditto to fill the seat expiring in December 2020 that had been held by Republican John Gunn until he resignedfrom office the previous month.

[45] In September 2016, the borough council selected John Rush Butler to fill the vacant seat expiring in December 2016 that had been held by Keith Miller until his resignation earlier that month; Butler will serve on an interim basis until the November 2016 general election, when voters will choose a candidate to serve the balance of the term of office.

[48][49][50] For the 119th United States Congress, New Jersey's 6th congressional district is represented by Frank Pallone (D, Long Branch).

[53] For the 2024-2025 session, the 11th legislative district of the New Jersey Legislature is represented in the New Jersey Senate by Vin Gopal (D, Long Branch) and in the General Assembly by Margie Donlon (D, Ocean Township) and Luanne Peterpaul (D, Long Branch).