How many ships were involved in the Portolà expedition?
Portolà expedition
On February 15, Gálvez dispatched the "San Antonio", captained by Juan Pérez, from Cabo San Lucas; Franciscan friars Juan Vizcaíno and Francisco Gómez served as chaplains. With sailors plus cooks, carpenters and blacksmiths, the "San Antonio" carried a total of around 30 men. These ships left ahead of the land groups. The "San Carlos" and "San Antonio" were followed by an additional supply ship, the "San José", which was named after the patron saint of the Portolá expedition, Saint Joseph. The "San José" never reached San Diego and was presumed lost at sea.
Battle of the Coral Sea
The Japanese Port Moresby Invasion Force, commanded by Rear Admiral Kōsō Abe, included 11 transport ships carrying about 5,000 soldiers from the IJA's South Seas Detachment plus approximately 500 troops from the 3rd Kure Special Naval Landing Force (SNLF). Escorting the transports was the Port Moresby Attack Force with one light cruiser and six destroyers under the command of Rear Admiral Sadamichi Kajioka. Abe's ships departed Rabaul for the trip to Port Moresby on 4 May and were joined by Kajioka's force the next day. The ships, proceeding at , planned to transit the Jomard Channel in the Louisiades to pass around the southern tip of New Guinea to arrive at Port Moresby by 10 May. The Allied garrison at Port Moresby numbered around 5,333 men, but only half of these were infantry and all were badly equipped and undertrained.
Leading the invasion of Tulagi was the Tulagi Invasion Force, commanded by Rear Admiral Kiyohide Shima, consisting of two minelayers, two destroyers, six minesweepers, two subchasers and a transport ship carrying about 400 troops from the 3rd Kure SNLF. Supporting the Tulagi force was the Covering Group with the light carrier , four heavy cruisers, and one destroyer, commanded by Rear Admiral Aritomo Gotō. A separate Cover Force (sometimes referred to as the Support Group), commanded by Rear Admiral Kuninori Marumo and consisting of two light cruisers, the seaplane tender and three gunboats, joined the Covering Group in providing distant protection for the Tulagi invasion. Once Tulagi was secured on 3 or 4 May, the Covering Group and Cover Force were to reposition to help screen the Port Moresby invasion. Inoue directed the "MO" operation from the cruiser , with which he arrived at Rabaul from Truk on 4 May.