Career
He was sent as a young officer to Louisiana, where he distinguished himself in the wars against the Chickasaws and was wounded in the battle of Ackia in 1736. In 1758, he settled as a planter in New Orleans, but the following year became embroiled in a quarrel with Governor Kerlerec, who accused him of insubordination and other offenses, for which he was thrown into prison for three years, and, in 1762, deported back to France to be prosecuted. In 1765 he was eventually imprisoned in the Bastille but only for two weeks.
Judgment in his trial was finally rendered in 1769, in his favor.
Soon after he was appointed lieutenant-colonel. Louisiana having been ceded to Spain, Grondel was appointed in 1772 to the command of the naval base at Lorient, and rose to the rank of brigadier-general in 1788.
In 1792, during the French Revolution, he was denounced as an aristocrat and thrown into prison, but once again, for just a few days. And almost immediately upon his release he was elected by the inhabitants of Nemours commanding general of the national guards of their city, serving until the following year.
Having quelled a riot in town between rival military units by firmness and personal courage, he was voted thanks by the municipal authorities for his noble conduct.
In 1796 he retired to Salins, near Montereau-Fault-Yonne, and died in 1807 at the age of 93.