Alexander the Great's invasion of north-western India took place during the reign of which ruler of the Nanda dynasty?

Introduction / Context:
This question belongs to the intersection of Indian and Greek ancient history. Alexander the Great invaded north-western India around 326 BCE, reaching regions such as Punjab. At that time, the powerful Nanda dynasty was ruling Magadha in eastern India. Knowing which specific Nanda ruler was on the throne helps to situate Alexander’s invasion within the broader chronology of early Indian empires.

Given Data / Assumptions:

• Alexander's invasion of India occurred around 326 BCE.
• The question asks which Nanda ruler was reigning then.
• Options: Mahapadma Nanda, Dhana Nanda, Ajatasatru, Bimbisara.
• We work with standard chronological reconstructions used in exam books.

Concept / Approach:
Mahapadma Nanda is considered the founder of the Nanda dynasty, and Dhana Nanda is typically described as its last ruler. By the time Alexander reached the north-west frontier, Dhana Nanda was ruling Magadha, known to Greek sources as a very wealthy but unpopular king. Ajatasatru and Bimbisara belonged to the earlier Haryanka dynasty and ruled long before Alexander's time. Therefore, the invasion chronologically aligns with the reign of Dhana Nanda.

Step-by-Step Solution:
Step 1: Recall that Alexander entered India in 326 BCE. Step 2: Remember that the Nanda dynasty controlled Magadha at that time, with its capital at Pataliputra. Step 3: Note that Dhana Nanda was the last Nanda ruler, preceding Chandragupta Maurya. Step 4: Recognise that Mahapadma Nanda was earlier in the dynasty and Ajatasatru, Bimbisara were from a previous dynasty altogether. Step 5: Conclude that Dhana Nanda was ruling Magadha during Alexander’s Indian campaign.

Verification / Alternative check:
Greek accounts mention a powerful king named “Agrammes” or “Xandrames,” often identified with Dhana Nanda, ruling a rich empire in the Ganga valley that Alexander chose not to attack directly. Indian historical narratives also position Chandragupta Maurya’s overthrow of the Nandas shortly after Alexander’s departure. This synchronisation of Greek and Indian sources firmly places Dhana Nanda on the throne during the Macedonian invasion, reinforcing our answer.

Why Other Options Are Wrong:
Option a (Mahapadma Nanda) was an earlier Nanda king, associated with expanding Magadha but not with the specific dates matching Alexander’s campaign. Option c (Ajatasatru) and option d (Bimbisara) were Haryanka rulers from the 6th–5th centuries BCE, significantly earlier than Alexander's time. They could not have been reigning in 326 BCE, which makes them historically incompatible with the event described.

Common Pitfalls:
Students sometimes confuse Mahapadma and Dhana Nanda because both names are tied to the Nanda dynasty's power and wealth. Another pitfall is to overlook dynasty names and pick an earlier famous Magadhan ruler such as Ajatasatru. To avoid these mistakes, remember a simple chain: Haryanka (Bimbisara, Ajatasatru) → later dynasties → Nandas (Mahapadma, Dhana Nanda) → Mauryas (Chandragupta). Within that chain, Alexander's invasion aligns with Dhana Nanda near the end of the Nanda rule.

Final Answer:
Alexander the Great invaded India during the reign of Dhana Nanda of the Nanda dynasty.