Muhammad I of Granada

Abu Abdullah Muhammad ibn Yusuf ibn Nasr (Arabic: أبو عبد الله محمد بن يوسف بن نصر, romanized: Muḥammad ibn Yūsuf ibn Naṣr; c. 1195 – 22 January 1273), also known as Ibn al-Ahmar (ابن الأحمر, lit. 'Son of the Red') and by his honorific al-Ghalib billah (الغالب بالله, lit. 'The Victor by the Grace of God'), was the first ruler of the Emirate of Granada, the last independent Muslim state on the Iberian Peninsula, and the founder of its ruling Nasrid dynasty. He lived during a time when Iberia's Christian kingdoms—especially Portugal, Castile and Aragon—were expanding at the expense of the Islamic territory in Iberia, called Al-Andalus. Muhammad ibn Yusuf took power in his native Arjona in 1232 when he rebelled against the de facto leader of Al-Andalus, Ibn Hud. During this rebellion, he was able to take control of Córdoba and Seville briefly, before he lost both cities to Ibn Hud. Forced to acknowledge Ibn Hud's suzerainty, Muhammad was able to retain Arjona and Jaén. In 1236, he betrayed Ibn Hud by helping Ferdinand III of Castile take Córdoba. In the years that followed, Muhammad was able to gain control over southern cities, including Granada (1237), Almería (1238), and Málaga (1239). In 1244, he lost Arjona to Castile. Two years later, in 1246, he agreed to surrender Jaén and accept Ferdinand's overlordship in exchange for a 20-year truce.

In the 18 years that followed, Muhammad consolidated his domain by maintaining relatively peaceful relations with the Crown of Castile; in 1248; he even helped the Christian kingdom take Seville from the Muslims. But in 1264, he turned against Castile and assisted in the unsuccessful rebellion of Castile's newly conquered Muslim subjects. In 1266 his allies in Málaga, the Banu Ashqilula, rebelled against the emirate. When these former allies sought assistance from Alfonso X of Castile, Muhammad was able to convince the leader of the Castilian troops, Nuño González de Lara, to turn against Alfonso. By 1272 Nuño González was actively fighting Castile. The emirate's conflict with Castile and the Banu Ashqilula was still unresolved in 1273 when Muhammad died after falling off his horse. He was succeeded by his son, Muhammad II.

The Emirate of Granada, which Muhammad founded, and the Nasrid royal house, lasted for two more centuries until it was annexed by Castile in 1492. His other legacy was the construction of the Alhambra, his residence in Granada. His successors would continue to build the palace and fortress complex and reside there, and it has lasted to the present day as the architectural legacy of the emirate.

Muhammad ibn Yusuf was born in 1195 in the town of Arjona, then a small frontier Muslim town south of the Guadalquivir, now in Spain's province of Jaén. He came from a humble background, and, in the words of the Castilian First General Chronicle, initially he had "no other occupation than following the oxen and the plough". During his early life he became known for his leadership activity on the frontiers and for his ascetic image, which he maintained even after becoming a ruler.

His clan was known as the Banu Nasr or the Banu al-Ahmar. According to later Granadan historian and vizier Ibn al-Khatib, the clan was descended from a prominent companion of the Islamic prophet Muhammad known as Sa'd ibn Ubadah of the Banu Khazraj tribe; Sa'd's descendants migrated to Spain and settled in Arjona as farmers.

However, the authenticity of this genealogy is not well documented and appears to be a later fabrication (probably from the Nasrid period of splendor) intended to glorify the dynasty and endow it with origins befitting the brilliance it achieved during that era. The Arabic sources that mention this genealogy all date from the 14th century and later, after the establishment of the dynasty. Furthermore, the sources that offer the most detail were written by Nasrid authors closely linked to the sultans of the Alhambra, especially Ibn al-Khatib. Other non-Andalusian Arab authors from outside the emirate also mention the noble lineage but state that its authenticity is unknown, although some authors do accept it as valid.

Muhammad was also known as Ibn al-Ahmar, or by his kunya Abu Abdullah.

Muhammad I was married to a paternal first cousin (a bint 'amm marriage), Aisha bint Muhammad, likely in 1230 or before, when he was still in Arjona. Their first son was Faraj (1230 or 1231–1256), whose early death was recorded to cause Muhammad considerable sadness. Their other children included Yusuf (birth unknown), who also died during Muhammad I's lifetime; Muhammad (the future Muhammad II, 1235 or 1236–1302) and two daughters Mu'mina and Shams. He also had a brother, Ismail (d. 1257), whom he appointed as governor of Malaga, and who was the male-line ancestor of a line of future sultans of Granada starting from Ismail I.