He is the son of lieutenant Joseph Sosthène Lamy (1818–1891), originally from Nancy, and of Elisabeth Giraud, from an old and notable Provençal family, whose father Louis Giraud, notary, had married Honorine Courmes, from Grasse, the latter was the daughter of Claude-Marie Courmes, mayor of Grasse from 1830 to 1835.

[1] Lamy's ambition to become an officer developed very early; at ten-years-old, he entered the Prytanée national militaire, where he won the first prize in Geography in the general concourse of all the department's school, a possible sign of his future colonial career.

The following year he was back in Algeria, where he became aide-de-camp to the General in command of the division quartered in Algiers in 1887, and resumed his previous interest in the Sahara and learned to exploit the qualities of the méharistes, the camel cavalry.

The following day the united French forces confronted Rabih az-Zubayr, a Sudanese warlord who had created an empire in the Chad Basin.

In 1970, Chad issued an undated gold 1,000 francs coin as part of its tenth independence celebrations.