Agrarianism is a social and political philosophy that advocates for rural development, a rural agricultural lifestyle, family farming, widespread property ownership, and political decentralization. Those who adhere to agrarianism tend to value traditional forms of local community over urban modernity. Agrarian political parties sometimes aim to support the rights and sustainability of small farmers and poor peasants against the wealthy, powerful and famous in society.

Some scholars suggest that agrarianism espouses the superiority of rural society to urban society and the independent farmer as superior to the paid worker, and sees farming as a way of life that can shape the ideal social values. It stresses the superiority of a simpler rural life in comparison to the complexity of urban life. For example, M. Thomas Inge defines agrarianism by the following basic tenets:

The philosophical roots of agrarianism include European and Chinese philosophers. The Chinese school of Agriculturalism (农家/農家) was a philosophy that advocated peasant utopian communalism and egalitarianism. In societies influenced by Confucianism that had as its foundation that humans are innately good, the farmer was considered an esteemed productive member of society, but merchants who made money were looked down upon. That influenced European intellectuals like François Quesnay, an avid Confucianist and advocate of China's agrarian policies, in forming the French agrarian philosophy of physiocracy. The physiocrats, along with the ideas of John Locke and the Romantic Era, formed the basis of modern European and American agrarianism.

Physiocracy (French: physiocratie; from the Greek for "government of nature") is an economic theory developed by a group of 18th-century Age of Enlightenment French economists. They believed that the wealth of nations derived solely from the value of "land agriculture" or "land development" and that agricultural products should be highly priced. Their theories originated in France and were most popular during the second half of the 18th century. Physiocracy became one of the first well-developed theories of economics.

François Quesnay (1694–1774), the Marquis de Mirabeau (1715–1789) and Anne-Robert-Jacques Turgot (1727–1781) dominated the movement, which immediately preceded the first modern school, classical economics, which began with the publication of Adam Smith's The Wealth of Nations in 1776.

The physiocrats made a significant contribution in their emphasis on productive work as the source of national wealth. This contrasted with earlier schools, in particular mercantilism, which often focused on the ruler's wealth, accumulation of gold, or the balance of trade. Whereas the mercantilist school of economics held that value in the products of society was created at the point of sale, by the seller exchanging his products for more money than the products had "previously" been worth, the physiocratic school of economics was the first to see labor as the sole source of value. However, for the physiocrats, only agricultural labor created this value in the products of society. All "industrial" and non-agricultural labors were "unproductive appendages" to agricultural labor.

Quesnay was likely influenced by his medical training, particularly by the work of William Harvey who explained how blood flow and the circulatory system is vital to the human body; Quesnay held that the circulation of wealth was vital to the economy. Societies at the time were also overwhelmingly agrarian. This may be why they viewed agriculture as the primary source of a nation's wealth. This is an idea which Quesnay purported to demonstrate with data, comparing a workshop to a farm. He analyzed "how money flowed between the three classes of farmers, proprietors, and artisans, in the same mechanical way that blood flows between different organs" and claimed only the farm produced a surplus that added to the nation's wealth. Physiocrats viewed the production of goods and services as equivalent to the consumption of the agricultural surplus, since human or animal muscle provided the main source of power and all energy derived from the surplus from agricultural production. Profit in capitalist production was really only the "rent" obtained by the owner of the land on which the agricultural production took place.

The United States president Thomas Jefferson was an agrarian who based his ideas about the budding American democracy around the notion that farmers are "the most valuable citizens" and the truest republicans. Jefferson and his support base were committed to American republicanism, which they saw as being in opposition to monarchy, aristocracy, clericalism and corruption, and which prioritized morality and virtue, exemplified by the "yeoman farmer", "planters", and the "plain folk". In praising the rural farmfolk, the Jeffersonians felt that financiers, bankers and industrialists created "cesspools of corruption" in the cities and should thus be avoided.