It all began back then… June 1930.
From the Door County Advocate:

Dagneau’s New Mill Opening Saturday Night

“The formal opening of The Mill, Minor Dagneau’s beautiful new place on the corner of Highway 17 and 78, north from here, will take place Saturday night. Souvenirs will be given to all who attend.

“Mr. Dagneau, who formerly owned the National Hotel here, states that his new place will specialize in Chicken Sandwiches and Fish Fries at all times and will serve special dinners for parties making advanced reservations.

“The building, which is 54 by 69, includes a lobby, small soft drink parlor, and excellent white maple dancing floor surrounded by 16 booths, a modern kitchen on the main floor and living quarters for the family on the second floor.

“The exterior, painted in cream with apple trimmings is set off by a Dutch mill tower itself lighted with white and green lights alternately flashing on and off. Highway 78 will be landscaped.

“The building is electrically equipped and has hot and cold running water. Contracts for The Mill were let to John Anschtuz, Ed B. Olsen, F.J. Stroh and Son, Barker Lumber and Fuel Company, R.Z. Dama, Fred Crandall was the architect.

“Mr. Dagneau is pleased with the work done.”[end of Advocate article]

Then… in 1963 The Mill is purchased by the Petersilka Family!

March 18, 1963

The Mill is purchased by Milton and Marie Petersilka

August 1, 1978

The Mill is purchased by Don Sr and Janice Petersilka

July 1, 1991 to Present

The Mill is owned and operated by Don Jr and Shelly Petersilka