Joseph Wandsleben, better known in his time as Joe Wandy, had operated bars at 721 North 27th Street and at 1006-1008 North 24th Street in the 1930s and 1940s. The bar on North 24th Street was known as the Chateau.

At some point after 1959, thebuilding at 1787 River Avenue, which had been the Sheltering Arms Home run by the Camden County Society for the Prevention of Cruelty to Children, was purchased, and a new bar was built, called The Chateau, by Frank Mars. Frank Mars had owned a luncheonette at 24th and River Avenue. His restaurant clientele followed him down the street to the new bar, which he ran with help from his wife, son, and brother-in-law.

The Chateau bar was in operation by 1966. I do not know if this new Chateau is in anyway connected with Joe Wandy's Chateau.

The Chateau has operated continuously since it opened up in the early 1960s. 

Thanks to Ken Pierce for providing information about the founding of The Chateau.