Introduction:
The Delhi Sultanate, which lasted from the 13th to the 16th century, saw the rule of several powerful and influential sultans. One such sultan was Muhammad-bin Tughlaq, who introduced plebeian elements in his nobility.

Explanation:
Muhammad-bin Tughlaq:
Muhammad-bin Tughlaq was the Sultan of Delhi from 1325 to 1351. He was known for his ambitious and unconventional policies, some of which were aimed at bringing about social and economic reforms in his kingdom.

Introduction of Plebeian Elements:
Muhammad-bin Tughlaq is known for introducing plebeian elements in his nobility. This means that he appointed commoners or individuals from lower social classes to important positions in the nobility. This was a departure from the traditional practice of appointing nobles and aristocrats to such positions.

Reasons for Introducing Plebeian Elements:
There were several reasons behind Muhammad-bin Tughlaq's decision to introduce plebeian elements in his nobility:

1. Meritocracy: Muhammad-bin Tughlaq believed in a system where positions of power and authority were given based on merit rather than social status or lineage. By appointing commoners to important positions, he aimed to create a more meritocratic system.

2. Distrust of Nobility: Muhammad-bin Tughlaq was known for his distrust of the nobility. He believed that the nobles were often driven by self-interest and were not necessarily loyal to the Sultan or the kingdom. By appointing commoners, he hoped to reduce the influence of the nobility and create a more loyal and reliable nobility.

3. Economic Reforms: Muhammad-bin Tughlaq was also known for his economic reforms, which included the introduction of a new currency and the establishment of new markets. By appointing commoners to important positions, he aimed to bring in individuals who had a better understanding of the economic issues faced by the common people and could implement his reforms effectively.

Conclusion:
Muhammad-bin Tughlaq's decision to introduce plebeian elements in his nobility was a unique and unconventional approach. While his intentions may have been noble, the success of this policy is debatable. Nevertheless, his reign was marked by significant social, economic, and administrative reforms, and his decision to appoint commoners to important positions was one of the many ways in which he tried to bring about change in his kingdom.