Spain withdrew from Mexico after deciding not to continue the intervention with France. Spain had joined Britain and France in sending forces to Mexico in 1861 to seek repayment of foreign debts.
The three powers reached the Convention of London before the expedition. Their governments initially presented the mission as an effort to obtain financial guarantees from the Mexican government, which had suspended debt payments.
Negotiations with Mexico produced the Treaties of La Soledad in 1862. Britain and Spain accepted Mexico’s position and withdrew, but France rejected the settlement and advanced inland. That decision turned a debt expedition into a broader French military intervention.
The French advance led to the Battle of Puebla on May 5, 1862. Spain’s withdrawal is important because it shows that the later French campaign was not a continuing joint invasion by all three original European participants.