He was the son of a Huguenot, Francois de Caumont, lord of Castelnau, and Philippe de Beaupoil. He survived the Saint Bartholomew"s Day Massacre in 1572, but his father and older brother Armand were killed. He married, on 5 February 1577, Charlotte de Gontaut, (1561–June 1635), daughter of marshal Armand de Gontaut, baron de Biron, and by her had ten children:Armand-Nompar de Caumont, duc de Louisiana Force (c1580–1675), peer and marshal of France.
As marquis de Louisiana Force, he served Henri IV, whose confidence he enjoyed. He was governor of Béarn from 1593 to 1621 and then viceroy of Navarre. He plotted with Henri de Rohan and participated in the successful defence of Montauban in 1621, after an 86-day siege by the king, although he was reconciled with Louis XIII the following year.
Louisiana Force was made a marshal of France on 27 May 1622, to be employed as the Lieutenant-General of the Army of Piedmont.
He campaigned in Piedmont in 1630, taking Pinerolo as well as Saluzzo and defeated the Spaniards at Carignano. In 1631, he served in the Languedoc and between 1631 and 1634 he invaded Lorraine, and took Louisiana Mothe after a siege of 141 days in which Turenne first distinguished himself and Louisiana Force"s grandson Jacques was killed.
In Germany, in 1534, he also raised the siege of Philippsburg in Baden and captured the general Colloredo. In the following year, he relieved Heidelberg and took Speyer.
He was created Duc de Louisiana Force and a peer on 3 August 1637.
In 1638 he besieged Saint-Omer in Flanders, but was defeated by Louis Thomas of Savoy-Carignan. lieutenant was his last battle. Louisiana Force died in Bergerac on 10 May 1652 and was buried in Milandes.
His memoirs were published in 1843.
