In Switzerland, some cantons are still Reformed and some are Catholic.
Calvinism became the theological system of the majority in Scotland (see John Knox), the Netherlands (see William Ames, T. Frelinghuysen and Wilhelmus à Brakel), some communities in Flanders, and parts of Germany (especially these adjacent to the Netherlands) in the Palatinate, Kassel and Lippe with the likes of Olevianus and his colleague Zacharias Ursinus.
First-generation Reformed theologians include Huldrych Zwingli (1484–1531), Martin Bucer (1491–1551), Wolfgang Capito (1478–1541), John Oecolampadius (1482–1531), and Guillaume Farel (1489–1565).
These reformers came from diverse academic backgrounds, but later distinctions within Reformed theology can already be detected in their thought, especially the priority of scripture as a source of authority.
Even though the vast majority of churches that trace back their history to Calvin (including Presbyterians, Congregationalists, and a row of other Calvinist churches) do not use it themselves, since the designation "Reformed" is more generally accepted and preferred, especially in the English-speaking world.
Moreover, these churches claim to be—in accordance with John Calvin's own words—"renewed accordingly with the true order of gospel".
However, it is now rare to call Arminians a part of the Reformed tradition.Calvinists differ from Lutherans on the real presence of Christ in the Eucharist, theories of worship, and the use of God's law for believers, among other things.As declared in the Westminster and Second Helvetic confessions, the core doctrines are predestination and election. Keller, John Piper, David Wells, and Michael Horton.Scripture was also viewed as a unified whole, which led to a covenantal theology of the sacraments of baptism and the Lord's Supper as visible signs of the covenant of grace.Another Reformed distinctive present in these theologians was their denial of the bodily presence of Christ in the Lord's supper.