There are numerous prehistoric vestiges of human occupation throughout the municipality of Idanha-a-Nova (Idanha "the new"), such as
menhirs and
tapirs.
The Romans had an important influence, namely in the civil parishes of
Monsanto,
Idanha-a-Velha (Idanha "the old", formerly known as the Roman
Civitas Igaeditanorum and the
Germanic Egitânia) and
Ladoeiro and in the countryside around the town of Idanha-a-Nova proper, where there was a
Roman villa, immortalized in an ancient
mosaic. After
the fall of the Roman Empire, the
Suevi and
Visigoths dominated, and is from that time the creation of the now extinct Bishopric of
Egitânia. In terms of architectural heritage, Egitânia (Idanha-a-Velha) stands out as an archaeological site from the year 534, which was one of the most important cities in
Lusitania at a time, with the remaining sections of Roman pavements and the Romanesque bridge, built over the
Ponsul River. In 1187, a castle was built by
Gualdim Pais, a Portuguese
crusader,
Knight Templar in the service of
Afonso Henriques of Portugal. King Sancho I (1185–1211) granted Idanha a
foral charter in 1201 in order to encourage the settlement and defence of the land. His successor,
King Afonso II (1211–1223) confirmed this charter in 1219 renaming the village with the current place names (Idanha-a-Nova) to distinguish it from the old Idanha (hereinafter Idanha-a-Velha), 18 kilometers away. The village of Idanha-a-Nova has developed a lot since then, at the same time Idanha-a-Velha went into steady decline. In the late fifteenth century, King
Manuel I of Portugal (1495–1521), was surprised with the difference in the development of the two Idanhas (1496) and in June 1510, recognizing the progress of Idanha-a-Nova, granted it new charter. At this time, the town and its castle, including the layout, was recorded down by
Duarte de Armas in his
Book of Fortresses in 1509. A border municipality with Spain, the whole area was theatre of war, skirmishes and invasions throughout several periods in
Portuguese history. A large part of the population of the entire area migrated to other parts of Portugal and foreign countries from the 1960s onwards. The massive exodus was due to economic reasons since the area remained cut-off from the rest of the country and neighboring Spain as well as largely underdeveloped throughout most of the 20th century. From the 2000s to the early 2020s, thanks to
EU structural and cohesion funds, inland Portugal's settlement policies, the rise of
tourism in Portugal and a wave of
foreign direct investment, the depopulation phenomenon was mitigated but the municipality is still characterized by stagnation in population growth and intense population ageing. ==Economy==