Arzawa was a region and political entity in Western Anatolia during the Late Bronze Age. In Hittite texts, the term is used to refer both to a particular kingdom and to a loose confederation of states. The chief Arzawan state, whose capital was at Apasa, is often referred to as Arzawa Minor or Arzawa Proper, while the other Arzawa lands included Mira, Hapalla, Wilusa, and the Seha River Land.

Arzawa is known from contemporary texts documenting its political and military relationships with Egypt and the Hittite Empire. The kingdom had a tumultuous relationship with the Hittites, sometimes allied with them but other times opposing them, in particular in concert with Mycenaean Greece which corresponds to Ahhiyawa of the Hittite sources. During the Amarna Period, Arzawa had achieved sufficient independence that Egypt opened direct diplomatic relations, addressing the Arzawan king Tarhuntaradu as "great king", a title reserved for peers. However, the kingdom was fully subjugated by Mursili II around 1300 BC.

The Kingdom of Arzawa was located in Western Anatolia. Its capital was a coastal city called Apasa, which is believed to have been Ayasuluk Hill at the site of later Ephesus. The hill appears to have been fortified during the Late Bronze Age and contemporary graves suggest that it was a locally important center, though much of the potential ruins are obscured by the later Basilica of St. John.

In Hittite texts, the term "Arzawa" is also used more broadly to refer to a group of kingdoms including Arzawa itself. Thus, modern-day scholars sometimes use the terms "Arzawa Minor" or "Arzawa Proper" to designate the main kingdom. The other "Arzawa Lands" included Mira, Hapalla, Seha, and in later periods Wilusa as well. At times, the Arzawa Lands appear to have banded together as a loose military confederation, which may have been led by the Kingdom of Arzawa itself. However, they were never fully united as a single kingdom, and did not always operate in solidarity with one another.

The zenith of the kingdom was during the 15th and 14th centuries BC. The Hittites were then weakened, and Arzawa was an ally of Egypt.

Around 1650 BC, the Hittite old kingdom ruler Hattusili I raided Arzawan territory. Documents regarding this incident provide the earliest known mention of Arzawa, which in this era was spelled as Arzawiya. Around 1550 BC, the Arzawans joined a broader uprising against the Hittite king Ammuna. However, they were subjugated by Tudhaliya I/II around 1400 BC, concurrently with the Assuwa Revolt.

A Hittite text known as the Indictment of Madduwatta discusses the exploits of an Anatolian warlord named Madduwatta in and around Arzawa during Tudhaliya's reign. The document recounts that Madduwatta launched multiple unsuccessful attacks on Arzawa before seeking a marriage alliance with the Arzawan king Kupanta-Kurunta. Maduwatta then allied with a certain Attarsiya, the man of Ahhiyawa; the latter country being widely accepted as Mycenaean Greece or part of it. In general during the period 1400-1190 BC Hittite records mention that the populations of Arzawa and Ahhiyawa were in close contact.

Around 1370 BC, during the reign of Tudhaliya III, Arzawa conquered a large portion of Western Anatolia. Their army swept across the Lower Land, into territories that the Hittites had never lost before, reaching as far as the border as the Hittite homeland.