Don Manuel de Oms y Santa Pau, 1st Marquis of Castelldosrius, Grandee of Spain (sometimes marqués de Castell dos Rius) (1651 – 24 April 1710) was a Spanish diplomat, man of letters, and colonial official. From July 7, 1707 to April 22, 1710, he was viceroy of Peru.
Manuel de Oms y de Santa Pau was born in Barcelona and belonged to a noble family of Catalonia. He was governor of Tarragona from 1677 and ambassador to Portugal from 1681. In 1698, Charles II, the last Habsburg king of Spain, named him ambassador to the court of Louis XIV in Paris. Oms was a francophile who favored the Bourbons in the War of the Spanish Succession. During the war, he took the part of the Duke of Anjou, the future Philip V of Spain. He it was who informed the French king that Charles had named the Duke of Anjou as his heir, with the words Señor, desde este momento no hay Pirineos ("Lord, from this moment there are no more Pyrenees.").Archived March 28, 2006, at the Wayback Machine.
As a reward for his support, the Philip V named him viceroy of Peru in 1704, although he did not occupy the post until 1707.
He took up his position as viceroy on July 7, 1707. He was able to send back an enormous sum of money (1,600,000 pesos) to the king to cover some of the costs of the war. This was possible in part because of the discovery of the mines in Caraboya. The collection of the money caused many protests, especially among the merchants, who brought suit against the viceroy many times in the Tribunal del Consulado. The merchants also opposed his opening of the port of Callao to French shipping.
To this problem were added others: the increase in French contraband and the English attacks on the coast, especially those of Charles Wager and Thomas Colb in 1708 and those of Woodes Rogers between 1709 and 1711. To deal with the attacks, the viceroy tried to form a navy, recruiting men by means of a levy.