Question: Minor Old Testament prophet Nahum wrote about the Assyrian city of Nineveh, which lies on the banks of which river?

Context paragraphs:
Nahum 3: Nahum 3 is the third and last chapter of the Book of Nahum in the Hebrew Bible or the Old Testament of the Christian Bible.  This book contains the prophecies spoken by the prophet Nahum, and is a part of the Book of the Twelve Minor Prophets.  This chapter describes the cause of the destruction of Nineveh.

Prophet Daniel (Michelangelo): The Prophet Daniel is one of the seven Old Testament prophet's painted by the Italian High Renaissance master Michelangelo (c. 1542–1545) on the Sistine Chapel ceiling.  The Sistine Chapel is in Vatican Palace, in the Vatican City.

Nineveh Governorate: Nineveh Governorate (Arabic: نینوى‎ ‎ ) is a governorate in northern Iraq that contains the ancient Assyrian city of Nineveh.  It was an integral part of Assyria from the 25th century BC to the 7th century AD, It has an area of 37323 km2 and an estimated population of 2,453,000 people in 2003.  Its chief city and provincial capital is Mosul, which lies across the Tigris river from the ruins of ancient Nineveh.  Tal Afar is the second-biggest city.  Before 1976, it was called "Mosul Province" and included the present-day Dohuk Governorate.

Nahum 1: Nahum 1 is the first chapter of the Book of Nahum in the Hebrew Bible or the Old Testament of the Christian Bible.  This book contains the prophecies spoken by the prophet Nahum, and is a part of the Book of the Twelve Minor Prophets.  This chapter describes the character of God in giving a fair judgment upon Nineveh.

Nahum 2: Nahum 2 is the second chapter of the Book of Nahum in the Hebrew Bible or the Old Testament of the Christian Bible.  This book contains the prophecies spoken by the prophet Nahum, and is a part of the Book of the Twelve Minor Prophets.

Nimrud: Nimrud ( ; Arabic: النمرود‎ ‎ ) is the Assyrian Neo-Aramaic name for the ancient Assyrian city of Kalhu (the Biblical Calah), located 20 mi south of the city of Mosul, and 3 mi south of the village of Selamiyah (Arabic: السلامية‎ ‎ ), in the Nineveh plains in northern Mesopotamia.  It was a major Assyrian city between approximately 1350 BC and 610 BC.  The city is located in a strategic position 6 mi north of the point that the river Tigris meets its tributary the Great Zab.  The city covered an area of 360 ha .  The ruins of the city were found within 1 km of the modern-day Assyrian village of Noomanea in Nineveh Province, Iraq.  This is some 30 km southeast of Mosul.

Bakhdida: Bakhdida (Syriac: ܒܲܓܼܕܹܝܕܵܐ‎ , Arabic:بخديدا) ] , also known as Baghdeda, Qaraqosh, or Al-Hamdaniya, is an Assyrian city in northern Iraq within the Nineveh Governorate, located about 32 km (20 mi) southeast of the city of Mosul and 60 km west of Erbil amid agricultural lands, close to the ruins of the ancient Assyrian cities Nimrud and Nineveh.  It is connected to the main city of Mosul by two main roads.  The first runs through the towns of Bartella and Karamles which connects to the city of Erbil as well.  The second, which was gravel until being paved in the 1990s, is direct to Mosul.

Nahum: Nahum ( or ; Hebrew: נַחוּם‎ "Naḥūm") was a minor prophet whose prophecy is recorded in the Hebrew Bible or Old Testament.  His book comes in chronological order between Micah and Habakkuk in the Bible.  He wrote about the end of the Assyrian Empire, and its capital city, Nineveh, in a vivid poetic style.

Rossano Gospels: The Rossano Gospels, designated by 042 or Σ (in the Gregory-Aland numbering), ε 18 (Soden), at the cathedral of Rossano in Italy, is a 6th-century illuminated manuscript Gospel Book written following the reconquest of the Italian peninsula by the Byzantine Empire.  Also known as Codex purpureus Rossanensis due to the reddish-purple ("purpureus" in Latin) appearance of its pages, the codex is one of the oldest surviving illuminated manuscripts of the New Testament.  The manuscript is famous for its prefatory cycle of miniatures of subjects from the "Life of Christ", arranged in two tiers on the page, sometimes with small Old Testament prophet portraits below, prefiguring and pointing up to events described in the New Testament scene above.

Nineveh: Nineveh ( ; Akkadian: "Ninua" ) was an ancient Assyrian city of Upper Mesopotamia, located on the outskirts of Mosul in modern-day northern Iraq.  It is located on the eastern bank of the Tigris River, and was the capital of the Neo-Assyrian Empire.  It is also a common name for the half of Mosul which lies on the eastern bank of the Tigris in the modern day.

Supporting paragraphs: Nahum Nineveh
Answer: Tigris