Whether they were a subset of the Sea People

"Sea Peoples" is a modern appellation. The Egyptians referred to some, but not all, of the migrating groups of the Late Bronze Age as "of the sea." The groups came from different regions of the eastern Mediterranean and, at various times, held different political allegiances. Lumping these groups together as a formless horde of "Sea Peoples" has not, I think, yielded very useful results. Egyptian, Assyrian, and biblical texts identify specific groups with specific locations (e.g. the Tjekker at Dor and Philistines at Gath), suggesting these groups were not interchangeable.

The Peleset are mentioned in several Egyptian inscriptions. At Medinet Habu Ramesses III recorded an invasion in Year 8 of his reign.

Their main support was Peleset, Tjekker, Shekelesh, Denyen, and Weshesh.

The groups were defeated, and the Egyptians depicted their bound prisoners. They even recorded (i.e. fabricated) the words of the defeated:

Speech of the defeated of Peleset: "Give us the breath for our nostrils, king, son of Amun!"

The Peleset appear again in the Harris Papyrus of Ramesses III.

I extended all the boundaries of Egypt. I overthrew those who invaded from their lands. I slew the Denyen in their islands, and the Tjekker and Peleset were turned into ashes. As for the Sherden and Weshesh, they were made into those who do not exist.

The Philistines also appear in the rhetorical stela of Ramesses III from Deir el-Medina and the Onomasticon of Amenemipet, a listing and categorization of gods, officials, Egyptian towns, buildings, types of produce, etc. The list of foreign groups includes the Philistines.

Philistines are, of course, most famously known from the Hebrew Bible/Old Testament. We learn interesting information about the Philistines from the OT, such as the pentapolis mentioned in 1 Samuel 6:17.

These are the gold tumors the Philistines sent as a guilt offering to the Lord—one each for Ashdod, Gaza, Ashkelon, Gath and Ekron.

The Philistines and the Israelites are portrayed as locked in combat, and the Philistines score some key victories, including briefly capturing the Ark of the Covenant (1 Samuel 4) and killing King Saul and his son (1 Samuel 31). Eventually, however, the Philistines were defeated.

Turning to the archaeological evidence, scholars have long considered Mycenaean IIIC:1 ware (also known as Philistine Monochrome ware) the identifying feature of Philistine settlements. Sherds of Mycenaean IIIC:1 ware were first found at Ashdod and consist of light-colored vessels decorated in one color (usually brown). About 50 years later, a new style developed that consisted of decoration of two colors on a light background. Circular bands and animal shapes are quite popular, particularly birds. This style is called Philistine Bichrome ware. Although the shape and decoration of Philistine monochrome ware were strongly reminiscent of Aegean pottery, a Neutron Activation Analysis study of the pottery demonstrated that the pottery was produced in Philistia.

Elements of architecture likewise suggest a link with the Aegean. The horned altars, for example, have a long history in the "horns of consecration" on Crete. Additionally, Aegean-style cooking pottery and hearths replaced local Canaanite wares and tabuns (ovens).

Finally, Philistine sites have yielded Aegean-style loom weights for textile production and pig bones that genetically match the pigs of Europe. (In other words, the migrants brought their pigs with them.)

A contentious topic in recent years is the existence of a "northern Philistia." The topic arose with the publication of ALEPPO 6, a hieroglyphic Luwian inscription from the temple of the Storm God in the citadel of Aleppo. The commissioner of the inscription, King Taita, refers to himself as "the king of Palistin."

REX Tá-i-tá-sa EGO-wa/i-mi (VIR2)HEROS (VIR2)pa-lá/í-sà-ti-[ní]-za-sa REX

"King Taita (am) I, Hero, Palistinean king."

The recently published inscriptions ARSUZ 1 and 2 also refer to Palistin (written as Walistin).

EGO-mi-i PURUS.FONS.MI-sá HEROS wa/i-lá/í-sà-ta-ni-za(REGIO) REX

"I am Suppiluliuma, hero, Walistinean king."

A fragmentary inscription referring to Palistin was also found at Tell Tayinat in the Hatay, where excavators found Mycenaean IIIC wares.

In short, it seems the Philistines were migrants from the Aegean at the end of the Late Bronze Age. Perhaps settling initially in Egypt (before they were repulsed and resettled) and Cyprus, they seem to have split into multiple waves of migration that wound up in northern Syria and the Amuq (the Kingdom of Palistin) and the pentapolis of the southern Levant.

References and further reading:

• The Philistines and Other Sea Peoples in Text and Archaeology edited by Ann Killebrew

• The Philistines and Aegean Migration at the End of the Late Bronze Age by Assaf Yasur-Landau
• "The inscriptions of the Aleppo temple" in Anatolian Studies 61 (2011): 35-54
• "Two new inscribed Storm-god stelae from Arsuz (İskenderun): ARSUZ 1 and 2" in Anatolian Studies 65 (2015): 59–77

Also check out the blog for the excavations at Tell es-Safi/Gath.