This what some of the leading Western scholars said about Prophet Muhamad

Prophet Muhammad is arguably the most under appreciated figure in the Western world as much as he is the most influential man in history. This is a collection of short quotable quotes from a wide variety of western Non-Muslim scholars from different professional groups and words spoken by academicians and professors from different subjects. They also include writers, philosophers, poets, politicians, and activists belonging to both the East and the West.
To our knowledge none of them ever became Muslims. These words, therefore, reflect their personal views on various aspects of the life of the Prophet.

Michael H. Hart (1932- ) was a Professor of astronomy, physics and the history of science. While ranking prophet Muhammad as The Most Influential Persons In History at New York in 1978 he said:
“My choice of Muhammad to lead the list of the world’s most influential persons may surprise some readers and may be questioned by others, but he was the only man in history who was supremely successful on both the religious and secular level.” [The 100: A Ranking Of The Most Influential Persons In History, New York, 1978, p. 33]

William Montgomery Watt (1909- ) was a Professor (Emeritus) of Arabic and Islamic Studies at the University of Edinburgh. In his book “Mohammad At Mecca” published by Oxford in 1953 on page 52, he wrote:
“His readiness to undergo persecutions for his beliefs, the high moral character of the men who believed in him and looked up to him as leader, and the greatness of his ultimate achievement – all argue his fundamental integrity. To suppose Muhammad an impostor raises more problems than it solves. Moreover, none of the great figures of history is so poorly appreciated in the West as Muhammad.”

Alphonse de Lamartine (1790-1869) was a French poet and statesman.
“Philosopher, orator, apostle, legislator, warrior, conqueror of ideas, restorer of rational dogmas, of a cult without images; the founder of twenty terrestrial empires and of one spiritual empire that is Muhammad. As regards all standards by which human greatness may be measured, we may well ask, is there any man greater than he?”[Translated from Histoire De La Turquie, Paris, 1854, vol. II, pp. 276-277]

Reverend Bosworth Smith (1794-1884) Late Fellow of Trinity College, Oxford.
“He was Caesar and Pope in one; but he was Pope without the Pope’s pretensions and Caesar without the legions of Caesar. Without a standing army, without a bodyguard, without a palace, without a fixed revenue, if ever any man had the right to say that he ruled by a right Divine, it was Mohammed; for he had all the power without its instruments and without its supports.” Mohammed and Mohammedanism, London, 1874, p. 235]

Mohandas KaramchandGandhi (1869-1948) was an Indian thinker, statesman, and nationalist leader. She wrote on her periodical “Young India” in 1928 that:
“….I became more than ever convinced that it was not the sword that won a place for Islam in those days in the scheme of life. It was the rigid simplicity, the utter self-effacement of the prophet, the scrupulous regard for his pledges, his intense devotion to his friends and followers, his intrepidity, his fearlessness, his absolute trust in God and in his own mission. These and not the sword carried everything before them and surmounted every trouble.”[Young India (periodical), 1928, Volume X]

Edward Gibbon (1737-1794) is considered the greatest British historian of his time. He wrote on his book “History Of The Saracen Empire published in 1870:

“The greatest success of Mohammad’s life was affected by sheer moral force without the stroke of a sword.”

John William Draper (1811-1882) was an American scientist, philosopher, and historian. He noted in his book “A History of the Intellectual Development of Europe” published 1875:

“Four years after the death of Justinian, A.D. 569, was born at Mecca, in Arabia the man who, of all men exercised the greatest influence upon the human race . . . Mohammed.” [A History of the Intellectual Development of Europe, London, 1875, vol.1, pp. 329-330]

David George Hogarth (1862-1927) was an English archaeologist, author, and keeper of the Ashmolean Museum, Oxford.
“Serious or trivial, his daily behaviour has instituted a canon which millions observe this day with conscious mimicry. No one regarded by any section of the human race as Perfect Man has been imitated so minutely. The conduct of the Founder of Christianity has not so governed the ordinary life of His followers. Moreover, no Founder of a religion has been left on so solitary an eminence as the Muslim Apostle. [Arabia, Oxford, 1922, p. 52]

Washington Irving (1783-1859) was Well-known as the first American man of letters”. He wrote in his famous book “Life of Mahomet”:
He was sober and abstemious in his diet, and a rigorous observer of fasts. He indulged in no magnificence of apparel (clothes), the ostentation of a petty mind; neither was his simplicity in dress affected, but the result of a real disregard to distinction from so trivial a source … In his private dealings he was just. He treated friends and strangers, the rich and poor, the powerful and the weak, with equity, and was beloved by the common people for the affability (friendliness) with which he received them, and listened to their complaints … His military triumphs awakened no pride nor vain glory, as they would have done had they been effected for selfish purposes. In the time of his greatest power he maintained the same simplicity of manners and appearance as in the days of his adversity. So far from affecting regal state, he was displeased if, on entering a room, any unusual testimonial of respect were shown to him.” [Life of Mahomet, London, 1889, pp. 192-3, 199]

Annie Besant (1847-1933) was a well known British theosophist and nationalist leader in India. President of the Indian National Congress in 1917.
“It is impossible for anyone who studies the life and character of the great Prophet of Arabia, who knows how he taught and how he lived, to feel anything but reverence for that mighty Prophet, one of the great messengers of the Supreme. And although in what I put to you I shall say many things which may be familiar to many, yet I myself feel whenever I re-read them, a new way of admiration, a new sense of reverence for that mighty Arabian teacher.” [The Life And Teachings Of Muhammad, Madras, 1932, p. 4]

Edward Gibbon (1737-1794) is considered the greatest British historian of his time. He noted in his book “History of the Decline and Fall of the Roman Empire”
“His (i.e. Muhammad’s) memory was capacious and retentive, his wit easy and social, his imagination sublime, his judgment clear, rapid and decisive. He possessed the courage of both thought and action.”[History of the Decline and Fall of the Roman Empire, London, 1838, vol.5, p.335]