Which ancient Indian ruler is traditionally credited with founding the city of Pataliputra, which later became a great imperial capital?

Introduction / Context:
Pataliputra, located near modern Patna in Bihar, was one of the most important cities of ancient India. It served as the capital under several major dynasties, including the Mauryas and the Guptas. Knowing who founded Pataliputra is a standard fact in ancient Indian history and appears frequently in competitive examinations. The question here has an incomplete original stem, which we have restored following the Recovery-First Policy as: “Who founded the city of Pataliputra?”

Given Data / Assumptions:

• The focus is on the founder of Pataliputra.
• Options include Udayin, Ashoka, Bimbisara and Mahapadma Nanda.
• We assume the usual chronological sequence of Magadhan rulers.
• We accept the textbook tradition that attributes the foundation of Pataliputra to Udayin.

Concept / Approach:
Bimbisara and his son Ajatashatru were early Magadhan rulers who shifted capitals and fortified important cities. However, the actual foundation of Pataliputra as a capital city on the confluence of the Ganga and Son rivers is generally credited to Udayin (also spelled Udayabhadra), a successor in the Haryanka line. Later, Pataliputra grew into a great metropolis under the Mauryas and others, but the initial founding is associated with Udayin. Thus, when asked directly who founded Pataliputra, the accepted answer in exam literature is Udayin.

Step-by-Step Solution:
Step 1: Recall that Pataliputra became the capital of Magadha and later of the Mauryan Empire.Step 2: Remember that Bimbisara and Ajatashatru were earlier rulers, but the actual founding of Pataliputra as a city is usually attributed to Udayin.Step 3: Recognise that Ashoka and Mahapadma Nanda ruled later; they used Pataliputra as a capital but did not found it.Step 4: Match these facts with the listed options to identify Udayin as the correct choice.Step 5: Select 'Udayin (Udayabhadra), a ruler of Magadha' as the final answer.

Verification / Alternative check:
Standard ancient Indian history textbooks and exam-preparation guides consistently state that Udayin founded Pataliputra. Many MCQs reproduce this fact directly with wording similar to this question. Cross-referencing multiple sources therefore confirms that Udayin is the expected answer in the context of Magadhan history and competitive examinations.

Why Other Options Are Wrong:
Ashoka the Great: He made Pataliputra a splendid imperial capital, but he did not found it; he ruled much later as a Mauryan emperor.Bimbisara: An important early king of Magadha, but the foundation of Pataliputra is usually credited to his successor Udayin.Mahapadma Nanda: Founder of the Nanda dynasty, he also ruled from Pataliputra but came later and cannot be considered the founder of the city.

Common Pitfalls:
One common error is to assume that the most famous ruler associated with a capital city must also have founded it. Students thus sometimes pick Ashoka simply because he is well-known. Another pitfall is mixing up different Magadhan rulers due to similar-sounding names or close chronological positions. To avoid this, memorise a short sequence of early Magadha history: Bimbisara, Ajatashatru, Udayin (founder of Pataliputra), and then later dynasties such as the Nandas and Mauryas.

Final Answer:
The city of Pataliputra was founded by the Magadhan ruler Udayin (Udayabhadra).