May Revolution
The May Revolution was a direct reaction to Spain's Peninsular War. In 1808, King Ferdinand VII of Spain abdicated in favor of Napoleon, who granted the throne to his brother, Joseph Bonaparte. A Supreme Central Junta led resistance to Joseph's government and the French occupation of Spain, but eventually suffered a series of reversals that resulted in the Spanish loss of the northern half of the country. On February 1, 1810, French troops took Seville and gained control of most of Andalusia. The Supreme Junta retreated to Cadiz and dissolved itself, and the Council of Regency of Spain and the Indies replaced it. News of these events arrived in Buenos Aires on May 18, brought by British ships.
May Revolution
The change was potentially favorable for Britain, as trade with the cities of the area was facilitated, without the monopoly that Spain had maintained over their colonies for centuries. However, Britain's first priority was the war against France in Europe, and they could not appear to support American independence movements or allow the military attention of Spain to be divided onto two different fronts. Consequently, they pushed to avoid explicit independence demonstrations. This pressure was exerted by Lord Strangford, the British ambassador at the court of Rio de Janeiro; he expressed support for the Junta, but under the condition that "...the behavior is consistent, and that [the] Capital [is] retained on behalf of Mr. Dn. Ferdinand VII and his legitimate successors". Later conflicts between Buenos Aires, Montevideo and Artigas led to internal conflicts on the British front, between Strangford and the Portuguese regent John VI of Portugal.