After some initial tactical success, the expedition, commanded by Captain Alberto Bayo, ended in failure when the Nationalists counterattacked with ground troops and massively superior air power and drove the Republicans into the sea.

So confident were the Republicans in their prediction of victory they optimistically called the operation "la reconquista de Mallorca" - "the reconquest of Majorca".

Plans for a seaborne attack on the Balearic Islands seem to have surfaced independently in various Republican militia groups in the days following the joining of Ibiza, Formentera, and Majorca to Franco's Nationalist military rebellion.

On August 2, Bayo assembled a column of Barcelona militia on Menorca; the next day, the Republican air force dropped bombs on Palma once more.

On 16 August, with various units of the Spanish Republican Navy in support, Bayo landed his force of 8,000 militia at Punta Amer and Porto Cristo.