What is the history of the term Palestine When was it first used to describe an area of land What is its etymology ?
The very first traces of the name Palestine come from the time of Ramses II and III, roughly around the mid-12th century BC. There is an inscription dated to around 1150 BC at the Medinet Habu temple in Luxor which refers to the Peleset (PLST) among those who fought against Ramses III. Today we know the Peleset as the Philistines.
A people called Peleset. From a graphic wall relief on the Second Pylon at Medinet Habu, c. 1150 BC, during the reign of Ramesses III.
Interestingly enough, it was long thought that the Philistines were sea-faring marauders, possibly Aegean in origin who invaded the Levant. This would neatly tie them into the Biblical narrative. However, there has been mounting evidence to suggest that the Philistines were actually an indigenous population originating in the region. According to advocates of this relatively new approach to the origins of the Philistines, the evidence has always been there, but in their haste to match archaeological evidence to the Biblical narrative many historians and archaeologists overlooked certain inconsistencies and contradictory evidence. You will find that much of the history of Palestine falls into this same trap, and many of the myths regarding Palestine todayemanate from trying to force a Biblical narrative onto history with little -if any- corroborating evidence.
Regardless of their origins, their name came to be associated with the area, not only in ancient Egyptian inscriptions, but also in ancient Assyrian inscriptions. For example, various Assyrian inscriptions from the 8th and 7th century BC refer to the area as “Palashtu”. This is the result of the Philistines’ influence and their intermingling and integration with the various peoples inhabiting the Levant. Prior to this, the area was more commonly known as Djahi, Retenu or Canaan, but beginning from the late Bronze age onwards, and as a result of said Philistine influence, the term Palashtu or Palestine came to replace them.
"In the fifth year (of my official rule) I sat down solemnly on my royal throne and called up the country (for war). I ordered the numerous army of Assyria to march against Palestine (Pa-la-áš-tu)... I received all the tributes […] which they brought to Assyria. I (then) ordered [to march] against the country Damascus (Ša-imērišu).
-Adad-nirari III. c. 800 BC.
"Bring down lumber, do your work on it, (but) do not deliver it to the Egyptians (mu-sur-a-a) or Palestinians (pa-la-as-ta-a-a), or I shall not let you go up to the mountains."
-Qurdi-Ashur-lamur to Tiglath-Pileser III, Nimrud Letter ND 2715. c. 735 BC.
According to Nur Masalha, their influence can still be felt today:
“..almost all the toponyms of the cities of Philistia: Gaza (Ghazzah), Askelon (‘Asqalan), Ashdod (Isdud), Tantur (Tantura), Gath (Jat), Ekron (‘Aqir) survived into the modern era and were preserved in the modern Palestinian Arabic names and were mostly depopulated by Israel in 1948.“
The name likely comes from a proto-Semitic word, albeit there is a strong similarity between Palaistī́nē and palaistês, the Greek word for "wrestler/rival/adversary".
It was during Classical Antiquity and the Hellenistic period (~500-135 BC) that the name “Palestine” as we know it today took form. The use of the terms Palaistine or Phalastin were widespread in the literature of the period. Philosophers and scientists such as Ptolemy and Aristotle spoke of Palaistine, and Herodotus’ Histories commonly used the name Palestine.
Herodotus, Histories Book II
Palestine in c.450 BC according to Herodotus (map as reconstructed by J. Murray, 1897)
In these writings, the use of the name Palaistine did not refer solely to the areas ruled by the Philistines at one point or another, but to widerswaths of the region, in some cases even stretching as far as what we would today call Jordan.
The name Palestine is the most commonly used from the Late Bronze Age (from 1300 BC) onwards. The name is evident in countless histories,‘ Abbasid inscriptions from the province of Jund Filastin, Islamic numismatic evidence maps (including ‘world maps’ beginning with Classical Antiquity) and Philistine coins from the Iron Age and Antiquity, vast quantities of Umayyad and Abbasid Palestine coins bearing the mint name of Filastin. The manuscripts of medieval al‑Fustat (old Cairo) Genizah also referred to the Arab Muslim province of Filastin. From the Late Bronze Age onwards, the names used for the region, such as Djahi, Retenu and Cana’an, all gave way to the name Palestine.Throughout Classical and Late Antiquity, the name Palestine remained the most common. Furthermore, in the course of the Roman, Byzantine and Islamicperiods the conception and political geography of Palestine acquired official administrative status.
Map is from Tuhfetü’l-Kibâr Fî Esfâri’l-Bihâr, which was written by Kâtib Çelebi. The book is on the Ottoman naval wars until 1656. Cities environs the Mediterranean and the Black Sea are mapped in the book. On the bottom right corner the word “Land of Falastin”, ”Quds Sharif”, “Gaza”, “Yafa” are mentioned.
There are many more examples of the usage of the term or its cognates, and it is not the intention of this answer to delve too deeply into the history of these uses. However, if you find the history of the name interesting then the further reading section in the comments below has some recommendations that you might find to your liking. Regardless, it is quite clear that this name originated well before the Romans or their conquest of Palestine.