He ordered the planting of a large pine forest (that still exists today) near Leiria to prevent the soil degradation that threatened the region and to serve as a source of raw materials for the construction of the royal ships.

[7] He advanced the interests of the Portuguese merchants, and set up by mutual agreement a fund called the Bolsa de Comércio, the first documented form of marine insurance in Europe, approved on 10 May 1293.

[12] In 1289 Denis had signed the Concordat of Forty Articles with Pope Nicholas IV, swearing to protect the Church's interests in Portugal.

[15] Denis negotiated with Clement's successor, John XXII, for recognition of the new order and its right to inherit the Templar assets and property.

[17][18] The first university in Portugal, then called the Estudo Geral (General Study), was founded with his signing of the document Scientiae thesaurus mirabilis in Leiria on 3 March 1290.

In 1284, however, Denis emulated the example of his grandfather and father, and launched a new series of inquiries to investigate the expropriation of royal property; this was to the detriment of the church.

[30] In 1288, Denis managed to persuade Pope Nicholas IV to issue a papal bull that separated the Order of Santiago in Portugal from that in Castile, to which it had been subordinate.

Denis pursued his father's policies on legislation and centralisation of power, and promulgated the nucleus of a Portuguese civil and criminal law code, protecting the lower classes from abuse and extortion.

[40] His wife Elizabeth donated much of the large income generated by her lands and properties to charities,[41][42] inspiring Denis to help improve the life of the poor and found several social institutions.

The restrictions he placed on the actions of alvazis (local council officials), judges, as well as proctors and advocates in the courts, show that a merely nominal power of the monarchy over all the inhabitants of the kingdom, as was typical in the Middle Ages, was not compatible with his effort to assert a royal prerogative to scrutinise legal procedures or moralise on the exercise of justice.

The appointment of magistrates clearly marks the start of the process of the crown claiming territorial jurisdiction, thus expanding the royal domain, along with the growing importance of Lisbon as the nation's de facto capital.

There was as yet no official capital of the country, but Lisbon's location, as well as its advanced urban, economic and commercial development, made the city the most viable choice for a national centre of administration.

One of his principal achievements was to protect agricultural lands from advancing coastal sands by ordering the planting of a pine forest near Leiria,[49] which also provided a source of raw materials for construction of a naval fleet.

As legend holds, in 1323, Elizabeth, mounted on a mule, positioned herself between the opposing armies on the field of the Battle of Alvalade in order to prevent the combat.

After he failed several times to mount an invasion of Portugal, the brothers signed a peace treaty, arranged by Afonso IV's mother Queen Elizabeth.

[57] Bearing in mind the many centuries that separate Denis from the present, an impression of his personality can be gathered from the historical record: he was determined, even obstinate, in his attempts to systematically centralise the government and consolidate royal power.

[58] For example, he launched general inquiries (Inquirições gerais) at a remarkably accelerated pace to investigate land ownership and identify cases where abuses were committed.

The wide range of his policies is indicated by a few examples: the concomitant creation of new towns and trade fairs, the fortification of the country's borders and the increasing dependence of the military orders on the royal power.

His actions were sufficiently [statesmanlike, and his political position was strong] enough, for him to secure the confiscation laws and check the erosion of the state patrimony".

He was described occasionally as cruel, especially in family relations, shown for example in the way he dealt with his legitimate son and rightful heir, Afonso (never his favourite), and his wife, Elizabeth, to whom he turned over the children born of his infidelities,[64] leaving her the responsibility of their care and education.

An inescapable figure in the history of the Iberian Peninsula in the 13th and the beginning of the 14th centuries, Denis was first called "father of his country" (Pai da Pátria) by the historian Duarte Nunes de Leão in 1600.

This genetic trait could have been passed on the maternal side, as his uncle Ferdinand, called "La Cerda", or "the bristly one", had red hair as well.