Final answer:
In Gandhi's 'Quit India' speech, the deity he refers to is 'Truth'. The Indian ruler who promoted Buddhism was Ashoka; the hymns brought by the Aryans are named Vedas; and the state of ultimate peace in Buddhism is nirvana.
Step-by-step explanation:
In Mahatma Gandhi's “Quit India” speech, the name he uses for the deity he is speaking of is ‘Truth’. He equates God with truth and thereby indicates that the religious and spiritual underpinnings of his call for non-violent resistance or "ahimsa,” are universally applicable beyond any single sectarian belief. Concerning the subject of the deity in Hinduism, neither Krishna nor Buddha could be called the founders of Hinduism; rather, Hinduism has no single founder and has evolved over thousands of years with contributions from many religious leaders and sages.
Regarding other historical questions, the Indian ruler who promoted the spread of Buddhism after his own conversion was Ashoka. The name of the hymns the Aryans brought to India is referred to as the Vedas. Lastly, Buddhists call the state of ultimate peace found in the extinction of all desire nirvana. The rulers of the Delhi Sultanate in India were followers of the Islamic religion, not Christianity or Buddhism.