He entered the ranks of the
Cuban Liberation Army on July 24, 1895, as a member of the expedition of the steamer
James Woodall, which landed in
Tayabacoa, on the south coast of
Las Villas, under the command of Major General
Carlos Roloff. He was assigned to the position of chief of staff of Major General
Serafín Sánchez, head of the first division of the fourth corps of Las Villas, with whom he participated in the actions of Taguasco and Los Pasitos. On September 3, 1895, Loynaz was elected as representative for Camagüey to the Constituent Assembly of Jimaguayú where he drafted the declaration of independence contained in the Constitution approved there. He joined the invading column with the position of aide-de-camp to Antonio Maceo. He also composed the
Himno Invasor on November 15, 1895. He participated in every battle around the earlier phases of the revolution, standing out in the battles of
La Reforma, Boca del Toro, El Quirro,
Mal Tiempo, Santa Isabel, La Colmena,
Coliseo, La Entrada,
Calimete and El Estante. In January 1896, he was appointed chief of staff of the fourth corps, continuing under the leadership of Serafín. He fought at Manajanabo, Dos Caminos, El Faro, Cascorro, El Marino and Manaquitas. On August 31, 1896, he presented a plan to the governing council to lead an armed expedition to
Puerto Rico. Considering that the conditions were averse to the probable success of such an enterprise, the governing council rejected it on September 14, 1896. He stood out in the
Battle of Paso de las Damas on November 18, 1896, where he charged against the Spaniards to rescue the lifeless body of Sánchez, after whose death he was temporarily in charge of the general inspection of the Liberation Army. On January 1, 1897, he was appointed second chief of the infantry of the expeditionary regiment, which operated in the
Matanzas Province, subordinate to Division General
Avelino Rosas, head of the first division of the fifth corps. A month later he was appointed chief of staff to Major General
José María Rodríguez, head of the Western Department. On June 24, 1897, he was appointed to replace Major General
Quintín Bandera with a view to which he reorganized the expeditionary contingent that was in Villareño territory, composed mainly of residents of the
Oriente Province. In August 1897 he again offered to invade Puerto Rico in conjunction with then-Brigadier General
José Lacret Morlot. In that year he fought the battles of Santa Teresa, Limones, Mercón, Quemados Grandes, Mabujina, Miranda, El Relámpago, Las Pozas, Valderrama, Punta del Hato, Ciénaga de Manjuarí, Río Voladora, Gϋinía de Miranda and La Jíquima, among others. On April 1, 1898, he rejoined his post as chief of staff of the Western Department, where the war ended. He took part in more than 60 combative actions. ==Later career==