What led Extremadurans to take a leading role in the conquest of Spain's territories in the Americas?

Question

According to Wikipedia, other sources, and politically-incorrect stereotypes the majority of the famous conquistadors were from the present-day Spanish autonomous community of Extremadura:

• Hernán Cortés
• Francisco Pizarro
• Hernando de Soto
• Pedro de Alvarado
• Pedro de Valdivia
• Álvar Núñez Cabeza de Vaca
• Alonso de Sotomayor
• Francisco de Orellana
• Vasco Núñez de Balboa

Note that Extremadura is landlocked and ships bound to the Americas typically departed from Andalusia's Atlantic coast:

Source: Wikimedia Commons

Source: Wikimedia Commons

Nevertheless, John Michael Francis mentions that the majority of conquistadors were from Andalusia:

The makeup of each expedition was similar, with an average of 30 percent from the southern Spanish kingdom of Andalusia, 19 percent from neighboring Extremadura, 24 percent from the core kingdoms of Old and New Castile, and the remainder from other regions in the Iberian peninsula. Other Europeans were rate, restricted to the odd Portuguese, Genoese, Flemish, or Greek man.

I can think of only a few conquistadors working for the Spanish Crown that were not from Extremadura:

• Christopher and Bartholomew Columbus were from Genoa
• Jaun de la Cosa was from Santoña in present day Cantabria
• Juan Ponce de León was from Santervás de Campos in present-day Castile and León
• Gonzalo Jiménez de Quesada and Sebastián de Belalcázar were from Cordova and the Pinzón brothers from Huelva, in Andalusia
• Alonso de Ojeda was from Cuenca in present-day Castile-La Mancha

What led Extremadurans to take a leading role in the conquest of Spain's territories in the Americas?

Answer 1

For many years, the Extremadura region was the border region between Christian and Moorish Spain. As a result, their inhabitants were quite literally "living at the edge." Hence they produced the largest number of "desperado" type conquerors.

It's like saying that America's most renowned Indian fighters (e.g. Buffalo Bill Cody or George A. Custer) were products of the American frontier, rather than the Atlantic seaboard. Or that the most renowned Mexico fighters like Davy Crockett were Texans.

Answer 2

I have been travelling in Extremadura for the past 5 days. What strikes me is the large number of rivers, some surprisingly large in June, most navigable. ALS remember the Romans took the trouble to come here overland and of course the Moors and the Castilians marched and counter marched this terrain for centuries. A theory I will advance is that after the conquest of Granada in1492 ( note the year) a lot of reconquistadors went home to the north. The more local Extremadurans might then have been closer to the new action and more tempted to try the 'new thing' than their more comfortable cousins who had gone back to the north and needed to hang about court to make sure they stayed in favour.