The conclusion of an agreement on February 12, 1871, for the submission to a mixed commission of claims of American citizens arising in Cuba,[116] took away all our pressing grievances against Spain and for more than two years our diplomatic relations were on a comparatively friendly basis. Good feeling between the two countries was further promoted by the proclamation of the Spanish republic in 1873 and by the prompt action of General Sickles in extending to it the recognition of the United States. After striving in vain for more than two years to reconcile and unite the contending factions of Spain, King Amadeus on February 11, 1873, abdicated the royal authority and returned to the nation the powers with which he had been intrusted. The Cortes at once proclaimed a republic. General Sickles had on January 30 telegraphed to Washington for instructions in case the republicans should succeed in their efforts. On the day after the abdication, he received directions to recognize the republican government when it was fully established and in possession of the power of the nation. Three days later, in the uniform of a major-general of the United States army he was given an audience by the president of the assembly and formally recognized the republic. On March 6, Congress by joint resolution, in behalf of the American people, tendered its congratulations to the people of Spain. It seemed at last as if our relations with Spain were on a good footing. General Sickles urged upon the new republican government the abolition of slavery and the concession of self-government to Cuba. But such cordial relations did not long continue. On October 31, 1873, the steamer _Virginius_, sailing under American colors and carrying a United States registry, was captured on the high seas by the _Tornado_, a Spanish war vessel, and on the afternoon of the first of November taken into the port of Santiago de Cuba. The men and supplies she bore were bound for the insurgents, but the capture did not occur in Cuban waters. General Burriel, the commandant of the city, summoned a court-martial, and in spite of the protests of the American consul, condemned to death at the first sitting four of the passengers, General W. A. C. Ryan, an Irish patriot and three Cubans. They were shot on the morning of November 4. On the 7th twelve other passengers were executed and on the 8th, Captain Fry and his entire crew, numbering thirty-six, making the total number of executions fifty-three. As soon as news of the capture reached Madrid, General Sickles called upon President Castelar and represented to him the difficulties that might arise in case the ship had been taken on the high seas bearing United States colors. Upon General Sickles's suggestion the President of the Spanish republic at once telegraphed to the captain-general to await orders before taking any steps in regard to the captured vessel and crew.