Díaz

Diaz is the son of a Diego, and Diego comes by a crooked road out of the Latin Didacus, to which the old patronymic ending -ici- was fastened. Galician kept both results of that join, Diz and Diaz; Portuguese kept its own, Dias.

The name is first found in the kingdom of Castile, the oldest traceable lineages belong to Leon, and Diaz is now the fourteenth most common surname in Spain. Outside Spain it went furthest in Chile, where by 2008 it was the fourth commonest surname in the country.

So many separate families carried the name that no single fountainhead can be fixed for it. The branch that held the lordship of Molina traced itself to Alfonso Diaz, one of the knights who took Baeza with the counts of Lara, who granted him lands at Peralejos.

The most consequential man the name ever produced was Rodrigo Diaz de Vivar, born around 1048 and called Diaz because his father was a Diego. Tradition puts his birth at Vivar, outside Burgos, but no source contemporary with him says so: Vivar is first attached to him around 1200, in the Cantar de mio Cid.

Ramon Menendez Pidal, in La Espana del Cid (1929), wanted a Rodrigo of humble stock, an infanzon of the minor Castilian nobility, to fit the hero of the poem who climbs from nothing into kinship with kings. The documents pull the other way. The Historia Roderici calls him a most illustrious man, and between 2000 and 2002 Margarita Torres matched the paternal ancestors it lists, Diego Flainez among them, against the Flainez of Leon, one of the four great families of that kingdom.

In 1058, still a boy, Rodrigo entered Fernando I's court as page to the infante Sancho. When the sons of Fernando I fell on each other over the divided kingdom he fought at the Castilian victories of Llantada in 1068 and Golpejera in 1072, the second of which put Alfonso VI in his brother's hands. Somewhere in those campaigns he acquired the byname Campeador, master of pitched battle, the only one of his titles attested in his own lifetime.

Sancho was killed at the siege of Zamora in 1072 and Alfonso VI took Castile back. The oath supposedly forced on Alfonso at Santa Gadea, the scene every Spanish schoolchild knows, is an invention; it first appears in 1236. The real relationship was cordial: Alfonso arranged his marriage to Jimena Diaz, a great-granddaughter of Alfonso V of Leon who carried the same surname he did, and sent him in 1079 to collect Seville's tribute, on which errand he beat Abdallah of Granada at Cabra and took the Castilian magnate Garcia Ordonez prisoner.

In 1080 he chased an Andalusi raiding party out of Soria, kept going into the taifa of Toledo, and sacked the eastern part of a kingdom under Alfonso's protection. That broke the bond of vassalage and cost him his exile. The counts of Barcelona would not have him, so he went to the Muslim king of Zaragoza, which was neither strange nor shameful: Alfonso VI had sheltered with the king of Toledo in 1072.

From 1081 to 1086 he fought for al-Muqtadir and then his son al-Mutamin at the head of his own mesnada, breaking the allied army at Almenar in 1082 then beating Sancho Ramirez of Aragon at Morella on 14 August 1084. It was on returning from one of those campaigns into a grateful Zaragoza that he may first have been greeted as sidi, my lord, the Andalusi Arabic word that romance mouths turned into Cid.

A second falling-out with Alfonso in 1088 brought a harsher exile: this time his property was confiscated, a penalty reserved for treason, and from that point Rodrigo acted for himself. In 1090 he broke and captured Berenguer Ramon II of Barcelona at Tevar, after which no Christian force in the east could touch him, and Valencia, Lerida, Tortosa, Denia, Sagunto and Segorbe all paid him tribute.

When the qadi Ibn Jahhaf seized Valencia on 28 October 1092 and put to death al-Qadir, Rodrigo's tributary and under his protection, the Campeador came back in a fury and closed a siege that lasted almost a year. The city capitulated on 17 June 1094 and he took it as a hereditary lordship, styling himself prince Rodrigo the Campeador. That September an Almoravid army under a nephew of the emir Yusuf came up to Cuart de Poblet and was beaten in open battle, and he beat them again at Bairen in 1097 alongside Pedro I of Aragon. His only son Diego Rodriguez was killed at Consuegra that same year.

In 1098 he made the old congregational mosque of Valencia into the cathedral of Santa Maria, and through his daughter's marriage to the infante Ramiro Sanchez his grandson Garcia Ramirez became king of Pamplona.

Rodrigo died at Valencia in 1099. Jimena Diaz inherited the lordship and held it until May 1102, when the family gave up, stripped and burned the city and left; the Almoravids walked in the next day and Valencia stayed in Muslim hands until 1238. His remains went with the refugees to San Pedro de Cardena, and since 1921 have lain with Jimena's in Burgos cathedral.

The literature began almost at once, and it worked by subtraction. The Carmen Campidoctoris, a Latin hymn of about 1190, praises him as a classical athlete and quietly drops his years serving the king of Zaragoza. The Cantar de mio Cid, written between 1195 and 1207, makes its hero a model of measure who seeks redress in court rather than blood; the swords Colada and Tizona, the horse Babieca and the birthplace at Vivar all appear there for the first time, and it is that Rodrigo, not the warlord in Zaragoza's pay, whom Corneille and the cinema inherited.

Alonso Diaz Moreno was born in 1526 at Valencia de Don Juan in the kingdom of Leon, the region the oldest Diaz lineages come from. He reached Santo Domingo in 1537, moved before 1551 to Santa Ana de Coro in the province of Venezuela, and on 25 March 1555, on the instruction of the governor Alonso Arias de Villasinda, founded the city of Valencia in Venezuela; the account rests on Jose de Oviedo y Banos's history of the province, published in 1723, and that is the date the city still keeps.

He held colonial office for the rest of his life: ordinary alcalde of Santiago de Leon de Caracas in 1574 and again in 1591, treasurer of the royal exchequer, lieutenant governor and captain general. His daughter Beatriz married Simon de Bolivar y Castro, putting his blood into the family that produced Simon Bolivar. He died at Caracas in 1602.

Porfirio Diaz, baptised at Oaxaca in September 1830, was the son of a criollo innkeeper of Spanish descent who died of cholera when the boy was three. He left the seminary for the law, studied under Benito Juarez, and commanded an infantry brigade by the time France invaded to install a client emperor. On 5 May 1862 he held one of the roads into Puebla with the Oaxaca battalion and threw back a French attack on the plain while the assault on the hill forts failed above him. When the French later offered him a place in their government, he refused it.

Captured twice by the French and escaped twice, he retook Oaxaca City in November 1866, stormed Puebla in the spring of 1867, and closed on Mexico City with 28,000 men, then refused to bombard it for seventy days rather than damage the capital. When it surrendered on 20 June he sent his army bakers out to feed the starving population. He was afterwards president of Mexico for more than thirty years, the longest tenure of any Mexican ruler.

Narcisse Virgilio Diaz de la Pena was born at Bordeaux in 1807 to Spanish parents, was orphaned at ten, and lost a leg to a badly dressed reptile bite in the wood at Meudon. At fifteen he went into the porcelain works at Sevres and painted his way out of them. What he wanted was the forest, and more than that he wanted to know how Theodore Rousseau painted it; he followed him through the trees at Fontainebleau on his wooden leg, spying on his method, until Rousseau was moved by the man's admiration and taught him everything he knew. He was made a chevalier of the Legion of Honour in 1851, and he is the painter Renoir meant when he said, my hero was Diaz.