Kshatriya (Sanskrit: क्षत्रिय, kṣatriya from Sanskrit: क्षत्र, kṣatra) or Kashtriya meaning warrior is one of the four varnas (social orders) in Hinduism. शर्म ब्राह्मणस्य वर्म क्षत्रियस्य गुप्तेति वैश्यस्य ). It constituted the military and ruling elite of Vedic-Hindu social system outlined by the Vedas and the Laws of Manu.
A Hindu ruler was bound by the holy scriptures to govern as a Dharma-Raja (Just Rule), with main duties being protection of his subjects and livestock.
The Rig Veda states:
praja arya jyotiragrah'. RV, VII. 33.17
People ruled by Aryans are led by the Divine light.
King Rama of Ayodhya is considered the greatest of the Dharma-Rajas:
arya sarva samascaiva sadaiva priyadarsanah
An Aryan who worked for the equality of all, was dear to everyone. Rama is also considered an avatar of Vishnu.
The word Arya (Aryan) means "Noble" (Noble/Lord/Perfect/Pure/Excellent...) and was initially only used for Kshatriyas (Kings & Nobles) as it is related to the word "Aristocracy".