Gallienus was a Roman Emperor who ruled from 253 to 268 AD. During his reign, he faced many challenges including civil wars, invasions, and economic crises. To address these challenges, he made several reforms, including military reforms. One of the reforms he made was to forbid senators from serving in the army or having access to it.

Reasons for forbidding senators from serving in the army:

1. Political instability: During Gallienus’ reign, there was a lot of political instability in Rome. The senators were often involved in political intrigues, which made them unreliable as soldiers. Gallienus feared that if he allowed senators to serve in the army, they would use their positions to advance their political interests and cause further instability.

2. Lack of military experience: The senators were not trained in military tactics and were not experienced soldiers. This made them less effective in battle and more likely to make mistakes that could cost lives.

3. Military corruption: In ancient Rome, military commanders often used their positions to enrich themselves and their families. Gallienus feared that if he allowed senators to serve in the army, they would use their positions to enrich themselves at the expense of the state.

Impact of the Reform:

The reform had several impacts, including:

1. Increased professionalism: By forbidding senators from serving in the army, Gallienus was able to increase the professionalism of the army. He recruited soldiers based on their military experience and training, rather than their political connections.

2. Improved efficiency: With professional soldiers, the army was able to operate more efficiently and effectively. This allowed Gallienus to respond more quickly to threats and crises.

3. Reduced corruption: By keeping senators out of the army, Gallienus was able to reduce corruption in the military. This helped to improve morale and ensure that the army was focused on its mission of defending the state.

In conclusion, Gallienus’ decision to forbid senators from serving in the army or having access to it was a wise one. It helped to increase the professionalism and efficiency of the army while reducing corruption and political instability.