Last updated: April 7th, 2025 at 4:06 pm · Est. Reading Time: 3 minutes
Arabian Peninsula (Jazīrat ul ‘Arab جَزِيرَةُ العَرَب) is a big chunk of land. Its boundaries are pretty fixed on three sides, where it is bound by sea.
To the west of it is the Red Sea, to the east is Persian Gulf. To the south the land is bound by the Arabian sea.
Northern boundary of Arabian Peninsula has been, and still is, controversial. An arbitrary boundary will be an imaginary line starting from Shat al Arab in the east, extending along the right bank of Euphrates up to Karbala, then bending on an obtuse angle to touch the lower limits of the Dead Sea, and lastly bending at an acute angle to reach the port of Aqaba in the west is the geographical northern boundary of Arabia.
Discussion
Earliest geographers were at a loss how to work it out. Herodotus (d. c. 425 BCE), for example, is vague in defining the northern border of Arabia. He defines Arabia as ‘the furthest of inhabited lands (oikumene) in the direction of midday’ delimited in the south by the ‘Erythrean Sea’, in the north by Assyria and Palestine, in the west by mountains bordering Egypt and the Arabian Gulf and in the east by Iran. Herodotus, by the way, had no knowledge of a gulf between Iran and Arabia.1
Pliny the Elder (d. 79 CE), aware of the dilemma around its northern boundary, gives the cultural boundary of the land rather than geographical one. He defines Arabia simply as the land of Arabs. Then he includes the Arabian Peninsula surrounded by the seas in the land of Arabs but extends its borders to the north to much of Syria, Mesopotamia and the eastern desert of Egypt – all regions occupied by Bedouins of the classic texts.2 Altheim and Stihl have worked out the extent of Bedouin distribution in 4th century CE.3 This work gives us an idea about which boundary line Pliny the Elder is presenting.
Bogged by the absence of any geographical structure limiting the northern extent of the land, lately, some writers are turning towards baffling geographical terms. For example, the upper boundary of Arabian tectonic plate or 200 mm/year isohyet (rainfall line).4
Problem here is that even if we successfully define the geographical northern boundary of Arabia, cultural and political boundaries – more important for a historian, will not toe this line. To be practical, we simply can assume that an imaginary line starting from Shat al Arab in the east, extending along the right bank of Euphrates up to Karbala, then bending on an obtuse angle to touch the lower limits of the Dead Sea, and lastly bending at an acute angle to reach the port of Aqaba in the west is the geographical northern boundary of Arabia. Saying so, the cultural and political boundaries of Arabia have always been changing, sometimes to the north of this line and other times to the south.
Further reading
Paul Sanlaville, “Geographic Introduction” in Roads of Arabia, ed. ‘Ali ibn Ibrāhīm Ghabbān, Beatrice Andre-Salvini Francoise Demange, Carine Juvin and Marianne Cotty, (Paris: Louvre, 2010), 55 – 68.
Peter Vincent, Saudi Arabia: An Environmental Overview, London: Taylor & Francis, 2007.
William Bayne Fisher, The Middle East. A Physical, Social and Regional Geography, London: Methuen & Co. Ltd, 1952.
History of Islam, Geography and Climate, 2025. https://historyofislam.org/geography-and-climate/
End notes
- Herodotus, Histories, ed. and trans. Henry Cary, (New York: Harper, 1859), P 96, 98, 101, 160 at paragraph 6, 12, 18, 159 in Book II (Euterpe); p 173, 215 at paragraph 9, 106 in Book III (Thalia); p 249 at Paragraph 37 in Book IV (Melpomene).
- Pliny, Natural History: vol. II, ed and trans. H. Rackham (London: William Heinemann, 1942), P 269 – 287, Book V, paragraphs XII to XXI.
- Franz Altheim and Ruth Steihl, Die Araber in der alten Welt: vol 2 (Berlin: W. de Gruyter, 1964), 344 – 356.
- For the titanic line see: Robert J. Stern and Peter Johnson, “Continental lithosphere of the Arabian Plate: A Geologic, Petrologic, and Geophysical Synthesis,” Earth-Science Review 101, no. 1 (2010): 29 – 67. For the isohyet see: Robert. G. Hoyland, Arabia and the Arabs: From the Bronze age to the coming of Islam (New York: Routledge, 2001), 3.