The memorable spot from whence the Lord called Abraham when an idolater. Sweet thought to the believer! It is JEHOVAH’S grace, and not man’s deserts, even in the instance of an Abraham, that is the sole cause of salvation. Some make Ur to mean light or fire, from Aor. (Gen. xi. 28.)
Ur, of the Chaldees, was the native place of the family of Abraham, whence he migrated first to Haran and then to Canaan (Gen 11:28; Gen 11:31; Gen 15:7; Neh 9:7; Act 7:4). It is supposed to be a district identical with the modern pashalic of Urfa, to which there belong several districts, among others Rouha, which is the ancient Edessa.
The country of Terah, and the birthplace of Abraham, Gen 11:28,31 15:7. It is usually called "Ur of the Chaldees," Heb 9:7 Mal 7:4 ; and is located, with strong probability, in the north-west part of Mesopotamia. The city of Orfah, to which the Jews make pilgrimages as the birthplace of Abraham, is a flourishing town of 30,000 inhabitants, seventy-eight miles south-west of Diarbekir. Some, however, place Ur in Lower Chaldea, at extensive ruins now called Warka, in latitude 31 degrees 19’ North, longitude 45 degrees 40’ East.\par
Ur. Ur was the land of Haran’s nativity, Gen 11:28, the place from which Terah and Abraham started "to go into the land of Canaan." Gen 11:31. It is called, in Genesis, "Ur of the Chaldaeans," while in the Acts, St. Stephen places it, by implication, in Mesopotamia. Act 7:2; Act 7:4. These are all the indications which Scripture furnishes as to its locality.
It has been identified by the most ancient traditions with the city of Orfah in the highlands of Mesopotamia, which unite the table-land of Armenia to the valley of the Euphrates. In later ages, it was called Edessa, and was celebrated as the capital of Abgarus or Acbarus who was said to have received the letter and portrait of our Saviour.
"Two, physical features must have secured Orfah, from the earliest times, as a nucleus for the civilization of those regions. One is a high-crested crag, the natural fortifications of the crested citadel. The other is an abundant spring, issuing in a pool of transparent clearness, and embosomed in a mass of luxuriant verdure, which, amidst the dull brown desert all around, makes and must always have made, this spot an oasis, a paradise, in the Chaldaean wilderness. Round this sacred pool, ’the beautiful spring Callirrhoe,’ as it was called by the Greek writers, gather the modern traditions of the patriarch." -- Stanley, Jewish Church, part i.p.7.
A second tradition, which appears in the Talmud, finds Ur in Warka, 120 miles southeast from Babylon and four east of the Euphrates. It was the Orchoe of the Greeks, and probably the Ereck of Holy Scripture. This place bears the name of Huruk in the native inscriptions, and was in the countries known to the Jews as the land of the Chaldaeans.
But in opposition to the most ancient traditions, many modern writers have fixed the site of Ur at a very different position, namely, in the extreme south of Chaldaea, at Mugheir, not very far above -- and probably in the time of Abraham actually upon -- the head of the Persian Gulf. Among the ruins which are now seen at the spot are the remains of one of the great temples, of a model similar to that of Babel, dedicated to the moon, to whom the city was sacred. (Porter and Rawlinson favor this last place).
Of the Chaldees (Gen 11:28; Gen 11:31; Gen 15:7; Neh 9:7), from which Terah, Abraham, and Lot were called. In Mesopotamia (Act 7:2). Now Mugheir (a ruined temple of large bitumen bricks, which also "mugheir" means, namely, Um Mugheir "mother of bitumen"), on the right bank of the Euphrates, near its junction with the Shat el Hie from the Tigris; in Chaldaea proper. Called Hur by the natives, and on monuments Ur. The most ancient city of the older Chaldaea. Its bricks bear the name of the earliest monumental kings, "Urukh king of Ur"; his kingdom extended as far N. as Niffer. The royal lists on the monuments enumerate Babylonian kings from Urukh (2230 B.C., possibly the Orchanus of Ovid, Met. 4:212) down to Nabonid (540 B.C.) the last. The temple was sacred to ’Urki, the moon goddess; Ilgi son of Urukh completed it.
For two centuries it was the capital, and always was held sacred. One district was "Ibra," perhaps related to "Hebrew," Abraham’s designation. Ur was also a cemetery and city of tombs, doubtless because of its sacred character, from whence the dead were brought to it from vast distances for 1,800 years. Eupolemos (in Eusebius, Praep. Ev. 9:17) refers to Ur as "the moon worshipping (kamarine; kamar being Arabic for moon) city." The derivation from Ur, "fire," led to the Koran and Talmud legends that Abraham miraculously escaped out of the flames into which Nimrod or other idolatrous persecutors threw him.
Ur lies six miles distant from the present coarse of the Euphrates, and 125 from the sea; though it is thought it was anciently a maritime town, and that its present inland site is due to the accumulation of alluvium (?). The buildings are of the most archaic kind, consisting of low mounds enclosed within an enceinte, on most sides perfect, an oval space 1,000 yards long by 800 broad. The temple is thoroughly Chaldaean in type, in stages of which two remain, of brick partly sunburnt, partly baked, cemented with bitumen.
Ur, light, land of light? Gen 11:28; Gen 11:31; Gen 15:7; Neh 9:7. Some have identified the city Ur with Edessa, the modern Orfah. Others suppose it to be Warka. But late explorations identify it with Mugheir, where considerable ruins exist. It is situated on the right bank of the Euphrates near the marshes, and in periods of inundation the ruins are surrounded by water. They are of an oval shape, and measure about half a mile from north to south. The temple ruins are in the form of a parallelogram 198 by 133 feet. The lower story is supported by thick buttresses; and the height of the whole is 70 feet. The exterior is faced with red kiln-baked bricks; and the interior is constructed of bricks burnt or sun-dried. The name of Urukh, an early king, 2230 b.c., has been found upon the bricks; and the place was probably the capital of this monarch. The temple was dedicated to the moon-god Hurki: hence perhaps the town derived its name.
By: Emil G. Hirsch
A locality mentioned four times in the Bible (Gen. xi. 28, 31; xv. 7; Neh. ix. 7) with the qualification 
(= "of the Kasdim," or Chaldees), and described as the original home of Abram. Modern scholars, with few exceptions, are agreed that Ur is identical with the mound of ruins in southern Babylonia on the right bank of the Euphrates, known as Al-Muḳair or Al-Mughair. This was an ancient seat of lunar worship; and it was dominant as a political center as early as 3000 B.C. Those scholars who incline to establish a connection between moon-worship ("Sin" = "moon") and the monotheism of Israel ("Sinai") find a corroboration of their theory in the fact that Abram's original home was the seat of the worship of Sin (comp. Jensen in "Zeitschrift für Assyriologie," xi. 298 et seq.).
Light
The ancient city of Ur was in the land of Chaldea, which was part of a larger territory commonly known as Babylon. Though it is mentioned in the Bible only as the place from which Abraham originally came (Gen 11:27-31; Gen 15:7; Neh 9:7), it was an important city in the ancient world. A powerful Sumerian dynasty had been centred there until overthrown by Amorites about 2000 BC. (For further details see AMORITES; BABYLON.)