On 18 November 1848, he married Cipriana du Cos de La Hitte (born 6 December 1829, Montevideo, Uruguay - died 23 October 1916) in the Church of Saint Ignatius, in Buenos Aires.

Luis Sáenz-Peña, a prominent Catholic leader, was anointed as a transitional president, after an agreement between Julio Argentino Roca's and Bartolome Mitre's factions that prevented the electoral participation of the brand new U.C.R.

He decided not to contract new debts, and personally renegotiated the existing ones in London: the financial situation forced the bankers to accept the conditions imposed by the Minister of Finance, Juan José Romero, who got some cuts in the capital and a somewhat longer term.

During his tenure, the Ministry of Public Works managed to expand the railway network, to the point that all provincial capitals — except La Rioja — were linked by rails.

In 1895, the political situation became more unstable every day, due to the evident incapacity of the president; Sáenz-Peña changed his entire cabinet of ministers several times, unsuccessfully seeking to avoid journalistic criticism.

Sáenz-Peña, increasingly disoriented, tried all possible alliances, and finally - before the imminence of a radical revolution - appointed Aristóbulo del Valle Minister of War and Navy.