[1] Matanhy was born on 24 October 1948, to Jacinto de Saldanha and Maria Alacoque Viegas in Carmona, Goa.

He later pursued higher studies in Christ College, Bangalore, where, aged around 17, he would share the money sent to him by his father with the poor, and teach them ways to be self-sufficient.

He formed the Goenchea Ramponnkarancho Ekvott (Association of Goa's Traditional Fisherfolk) and helped stop the discharge of effluents from the Zuari Agro Chemicals factory into the Arabian Sea, near Velsao.

In 2002, he was elected as a member of the legislative assembly from Cortalim constituency[15] as a candidate of the United Goans Democratic Party (UGDP).

[18] In February 2005, then Governor of Goa S. C. Jamir dismissed the Manohar Parrikar-led government after high allegations in the state legislature.

Saldanha was disqualified by then Speaker of the Goa Legislature, Francisco Sardinha, in August 2005 upon a disqualification petition filed against him by Jitendra Deshprabhu, spokesperson of the Indian National Congress.

[23][24] He later joined the Bharatiya Janata Party[25] and contested as a BJP candidate from the Cortalim constituency in the 2012 Goa Legislative Assembly election.

[citation needed] After Matanhy died in harness, his widow Alina Saldanha contested by-elections from the Cortalim constituency as a BJP candidate and was elected unopposed to the Goa State Legislature.

[31] After attending the xigmo (spring festival) in Canacona the previous night, Matanhy suffered a massive heart attack in the early hours of 21 March 2012, and died at 3 am in Campal, Goa.

[citation needed] A statue of Matanhy Saldanha was inaugurated by the then Chief Minister of Goa, Manohar Parrikar at Cansaulim on 24 October 2014.