Born to a very poor family he enrolled in the army at the young age of 15 using his mother's name, Contreras. J.B. Trend's account is that he ran away to enlist after stabbing a school-fellow in Madrid at the age of 13. He traveled to Flanders but soon deserted and traveled to Malta where, for the following six years, he would soldier in privateering ships under the banner of the Order of Malta. During this time he encountered countless risks, fights and adventures. He deserted several times, mainly due to fights in which he was involved. He also learned navigation by observing the pilots do their work and was soon given command of ships. He knew the eastern Mediterranean very well and used this knowledge to write a sailing directions of the entire Mediterranean. The original manuscript of this work is kept today, together with the original manuscript of his autobiography, at the Spanish National Library in Madrid. After six years he returned to Castile where he applied for and got a commission as an ensign and he visited his mother. His orders were to recruit his soldiers, as was customary then, and, under the command of his captain, go toExtremadura. There is an obscure incident where, in the small Morisco town of Hornachos, he found a cache of arms in a house where one of his soldiers was quartered. He was told by the local authorities to say nothing but years later he was accused and tried for plotting a rebellion. He is not very clear on this incident and it could well be that there was more to it than he intimates. A prostitutefalls in love with him after she sees him involved in a fight and joins him and follows him with his army but his captain tries to rape her and Contreras takes revenge by almost killing him. Contreras then escapes to Madrid where he gives himself up and explains what happened. He is exonerated and given order to return but most of the soldiers had deserted. After some time of soldiering he becomes a hermit on the slopes of the Moncayo in Aragon and lives that life until he is arrested and tried for the incident of the arms at Hornachos. He continued to have an adventurous and active military career which took him to many parts in Europe, rising to the rank of infantry captain. He also became an accomplished sailor and sailed all over the Mediterranean where he encountered many adventures. He also sailed to the West Indies where he encountered and fought the ships of Sir Walter Raleigh. For a time he was the governor of a small city in Italy. In Italy he married a Castilian lady but, having become suspicious of her faithfulness he spies on her and laconically says "their fate was that I found them in bed together and they died". He was present at the eruption of the Vesuvius volcano of 1631 and helped save some lives. He was befriended by the poet Lope de Vega who, having heard his tales, was probably who prompted him to write his autobiography.
