Then don Antonio Olaguer Feliú was named Viceroy of the Río de la Plata, a position he occupied between May 2, 1797, and May 14, 1799.
During his mandate, he had to contend with the presence of British and Portuguese forces in the Río de la Plata region, as well as nascent revolutionary sentiment inspired by the recent French Revolution. He opened the port of Buenos Aires to foreign traffic in a bid to stimulate the commercial activities of the Viceroyalty, which had begun to suffer from the growing tensions between the European powers.
The shield was party per pale. The first party was quartered. In the first and fourth quarters, there was a mount in natural colors on an argent field. In the second and third quarters, there were an argent oval roundel surrounded by eight argent stars on a gules field. In the second party, there were five argent castles triple towered in saltire on a gules field. External ornaments: the shield had six flags and two banners characteristic of Field Marshals and other ornaments (guns, spears, halberd, sword, drums, etc.) of the profession of arms. The coat of arms had a helmet with seven bars and surmounted by a Field Marshal coronet.[3][4]
Alvarez Massini, Ruben; Sanson, Alfredo C. (1977). Boletín Histórico del Ejército del Uruguay Nº 185-188 (in Spanish). Montevideo: Estado Mayor del Ejército, Departamento de Estudios Históricos "División Historia".