You are likely thinking of Mohammad Reza Pahlavi, last Shah of the Imperial State of Iran, who was ousted in the Islamic Revolution of 1979 by the force of Ayatollah Khomeini who then established the Islamic Republic of Iran.

The Shah was an interesting figure by all accounts. He ascended to hso throne after a Western-backed coup deposed of Mohammad Mosaddegh, Iran's socialist prime minister, due to the latter's intention of nationalizing Iran's oil fields, which were under the ownership of British oil companies.

As you mentioned, he was fascinated with the West and with the idea of modernizing Iran, which he intended to do in the so-called White Revolution beginning in 1963. This was a series of radical reforms which included a major land reform which intended to improve the status of some of Iran's poorest by the distribution of crown lands, the disposition of public lands (1956) as well as reforming some Iran older laws regarding land purchase. Additionally the Shah invested in modernizing Iran's infrastructure as well as its military.

The White Revolution succeed in some of its goals, but failed in othera. The old aristocracy's stranglehold over agricultural land was simply replaced by a new oligarchy of commercial farmers, including the Shah's on family, and little land actually made it into the hands of the peasantry. Additionally, the large focus on industry, which was largely unsuccessful, over Iran's traditional agriculture lead to widespread dissatisfaction with the Shah among the rural population of Iran. The Shah's policy of importing goods from the West, especially produce, also induced no small amount of ire from both the peasantry and the old landed elites.

The Shah's tendecy to ignore the opinions of the clergy, such as in his reforms of Iran education system which reduced the power of the clergy in it, further served to alienate him from the rural population, which tended to be far more religious than that of the urban centres. Khomeini spoke publicly against many aspects of the reforms, which led to his arrest and eventual exile in 1964. The Shah's focus on his reforms, his crushing of dissent by Iran's traditional elements and his perceived negligence of the rural population eventually led to the Islamic Revolution, after which he went into exile and eventually passed away at the age of 60 in Egypt.

For further reading, see:

What Really Happened in Iran: The CIA, the Ouster of Mosaddeq, and the Restoration of the Shah, by Ray Takeyh, Foreign Affairs Vol. 93, No. 4 (JULY/AUGUST 2014), pp. 2-12 for an account of the circumstances of the Shah's ascension,

Iran's White Revolution, by Kurush Shahbaz, World Affairs Vol. 126, No. 1 (Spring, 1963), pp. 17-21 for a contemporary account of the White Revolution.