[2] His grandfather, the 9th Marquess of Portago, had been Mayor of Madrid, while his father, who was President of Puerta de Hierro[3] and a prolific golfer, died of a heart attack while showering after a polo match.

At age 17, Portago began displaying his flamboyant lifestyle by winning a $500 bet after flying a borrowed plane under London Tower Bridge.

[4] He twice rode the Grand National as "gentleman rider" and formed the first Spanish bobsleigh team with his cousins, finishing 4th in the 1956 Winter Olympics, missing the bronze medal by 0.14 seconds.

His promising career was cut short in May 1957 after his renowned Ferrari 335 S crashed near the village of Guidizzolo when a tyre burst while driving along a dead straight road at 150 mph (240 km/h) in the 1957 running of the Mille Miglia, killing Portago, his navigator, and nine spectators.

[6] The young age of the marquess, who was 28 at the time of his death, combined with his status as a sex symbol,[7] caused a shock amongst many.

[8] The Marquess of Portago was seen by many as a true playboy of his time;[9][10][11] "a tall, handsome and wealthy Spanish aristocrat who captured everybody's imagination".

His father was Antonio Cabeza de Vaca, 10th Marquess of Portago, who died during half time at a polo match at a young age.

[16] Portago began racing sports cars in 1953 after his meeting with the Ferrari importer in the USA, Luigi Chinetti, who asked him to be his co-driver in the Carrera Panamericana.

His best result was a second place at the 1956 British Grand Prix (a shared drive with Peter Collins), and scored a total of four championship points.

With Portago steering, the two-man bob finished fourth to the surprise of the traditional teams, missing out on a medal by 0.16 seconds.

[21] He was introduced to bobsledding by an American from Beloit, Wisconsin, Edmund Nelson, whom he later teamed up with in order to win the Tour de France automobile race.

He and his co-driver Edmund Nelson (1916-1957) were killed on 12 May 1957[22] in a crash during that year's Mille Miglia, in a straight road section between Cerlongo and Guidizzolo, in the communal territory of Cavriana[14] about 70 km from Brescia, the start and finish point of the event race.

[6] Two of the dead children were hit by a concrete highway milestone that was ripped from the ground by Portago's car and thrown into the crowd.

[16] The Portago curve at the St. Moritz-Celerina Olympic Bobrun is named in his honor for his foundation's efforts to renovate the lower portion of the track.

[31][32][33] Supposedly, Carroll McDaniel and Alfonso de Portago were in the process of getting a divorce so he could legitimize his invalid Mexican marriage to fashion model Dorian Leigh (who had already aborted their first pregnancy in 1954 and then gave birth to their son Kim on 27 September 1955).