Here is a photo of the historical marker at Mandeville harbor commemorating the event.
In August of 1971 Judge S. F. Ellis of Covington gave a speech entitled "Seven Flags Over St. Tammany Parish" for the Historical Preservation Society. It dealt with the events that took place around St. Tammany during the period of time of the American Revolutionary War (1775 to 1783). Here are some of the more interesting historical facts:
"After the Revolutionary War began, James Willing of Philadelphia, representing the colonies, came down the Mississippi River in an attempt to have the English settlers there join in the Revolution. Although he was cordially received, he met with little success. He later returned, with a small force of men, and attacked and burned the plantations, and otherwise terrrorized the settlers along the river.
"Among his other feats, he captured a British sloop, the Rebecca, and brought it to New Orleans, where he was cordially received by Bernardo de Galvez, the young Spanish governor.
"In 1779, Spain declared war on England, and Galvez captured the British forts at Manchac and Baton Rouge, the latter on September 21, 1779. In the meanwhile, the sloop Rebecca, re-named the Morris, was placed under the command of William Pickles, flying the colors of the United States.
"He entered Lake Pontchartrain and challenged the British sloop "West Florida," which, by virtue of being the only armed vessel in the lake, had dominated commerce thereon. Although outgunned and outnumbered, Pickles fired upon, boarded and captured the "West Florida." He then proceeded to the north shore of the lake, where he forced the British settlers to swear allegiance to the United States, and claimed the territory.
"This happened on the same day that Galvez captured Baton Rouge."
Judge Ellis had delivered this material because of its relevance to the upcoming Bicentennial Celebration in 1976. In fact, one of the events held during the Bicentennial Celebrations in St. Tammany was a re-enactment of that 1779 event where Captain Pickles came ashore at Mandeville lakefront and read the proclamation to the British settlers that they were now Americans.
A photo showing the boat landing at Mandeville during that re-enactment is below.
And here is an article detailing the oath that Captain Pickles demanded of the St. Tammany Parish British citizens in pledging allegiance to the newly-formed United States of America. Click on the image to view a larger version.
The 1976 Re-enactment of Reading the Proclamation Above