And Calvin did not found it.
Here are a couple of quotes from a solid scholarly source on the subject:
"CALVINISM is an ambiguous term in so far as it is currently employed in two or three senses, closely related indeed, and passing insensibly into one another, but of varying latitudes of connotation. Sometimes it designates merely the individual teaching of John Calvin. Sometimes it designates, more broadly, the doctrinal system confessed by that body of Protestant Churches known historically, in distinction from the Lutheran Churches, as the Reformed Churches (see Protestantism); but also quite commonly called the Calvinistic Churches because the greatest scientific exposition of their faith in the Reformation age, and perhaps the most influential of any age, was given by John Calvin. Sometimes it designates, more broadly still, the entire body of conceptions, theological, ethical, philosophical, social, political, which, under the influence of the master mind of John Calvin, raised itself to dominance in the Protestant lands of the post-Reformation age, and has left a permanent mark not only upon the thought of mankind, but upon the life-history of men, the social order of civilized peoples, and even the political organization of states. In the present article, the term will be taken, for obvious reasons, in the second of these senses. Fortunately this is also its central sense; and there is little danger that its other connotations will fall out of mind while attention is concentrated upon this."
Warfield, B. B. (2008).
The Works of Benjamin B. Warfield: Calvin and Calvinism (Vol. 5, p. 353). Bellingham, WA: Logos Research Systems, Inc.
"Historically the Reformed theology finds its origin in the reforming movement begun in Switzerland under the leadership of Zwingli (1516). Its fundamental principles are already present in Zwinglis teaching, though it was not until Calvins profound and penetrating genius was called to their exposition that they took their ultimate form or received systematic development. From Switzerland Calvinism spread outward to France, and along the Rhine through Germany to Holland, eastward to Bohemia and Hungary, and westward, across the Channel, to Great Britain. In this broad expansion through so many lands its voice was raised in a multitude of confessions; and in the course of the four hundred years which have elapsed since its first formulation, it has been expounded in a vast body of dogmatic treatises. Its development has naturally been much richer and far more many-sided than that of the sister system of Lutheranism in its more confined and homogeneous environment; and yet it has retained its distinctive character and preserved its fundamental features with marvelous consistency throughout its entire history. It may be possible to distinguish among the Reformed confessions, between those which bear more and those which bear less strongly the stamp of Calvins personal influence; and they part into two broad classes, according as they were composed before or after the Arminian defection (ca. 1618) and demanded sharper definitions on the points of controversy raised by that movement (see Arminius, Jacobus, and Arminianism; Remonstrants). A few of them written on German soil also bear traces of the influence of Lutheran conceptions. And, of course, no more among the Reformed than elsewhere have all the professed expounders of the system of doctrine been true to the faith they professed to expound. Nevertheless, it is precisely the same system of truth which is embodied in all the great historic Reformed confessions; it matters not whether the document emanates from Zurich or Bern or Basel or Geneva, whether it sums up the Swiss development as in the second Helvetic Confession, or publishes the faith of the National Reformed Churches of France, or Scotland, or Holland, or the Palatinate, or Hungary, Poland, Bohemia, or England; or republishes the established Reformed doctrine in opposition to new contradictions, as in the Canons of Dort (in which the entire Reformed world concurred), or the Westminster Confession (to which the whole of Puritan Britain gave its assent), or the Swiss Form of Consent (which represents the mature judgment of Switzerland upon the recently proposed novelties of doctrine). And despite the inevitable variety of individual points of view, as well as the unavoidable differences in ability, learning, grasp, in the multitude of writers who have sought to expound the Reformed faith through these four centuriesand the grave departures from that faith made here and there among themthe great stream of Reformed dogmatics has flowed essentially unsullied, straight from its origin in Zwingli and Calvin to its debouchure, say, in Chalmers and Cunningham and Crawford, in Hodge and Thornwell and Shedd."
Warfield, B. B. (2008).
The Works of Benjamin B. Warfield: Calvin and Calvinism (Vol. 5, pp. 360362). Bellingham, WA: Logos Research Systems, Inc.