At the outbreak of the Spanish Civil War in Alicante he founded the Maroto Column, initially composed of 270 anarcho-syndicalist militiamen. At the command of this column, he moved to the Granada front and came to operate in the area of Guadix. There he took charge of other anarchist militias and was able to recruit more volunteers until reaching 1,000 officers. Although he intervened in the attack against Güéjar Sierra, he was never able to take the city of Granada —the objective of his column.
