The Wisconsin Evangelical Lutheran Synod (WELS) is a North American religious denomination with practice rooted in the Lutheran tradition of Christianity. Characterized as theologically conservative, it was founded in 1850 in Wisconsin. As of 2005, it had a membership of over 398,000 in more than 1,200 congregation, in all 50 U.S. states as well as 24 countries. It is the third largest Lutheran denomination in the United States, following Evangelical Lutheran Church in America (ELCA) and Lutheran Church - Missouri Synod (LCMS).
WELS is in fellowship with the Evangelical Lutheran Synod (ELS), a smaller denomination based in south-central Minnesota, and is a member of the Confessional Evangelical Lutheran Conference (CELC), a worldwide organization of Lutheran church bodies. It should be noted that the WELS, along with the LCMS, are independent Lutheran denominations and are not a part of the ELCA, which is structured to have "synods" within the denomination. Thus, the term "synod" used by the ELCA refers to administrative districts in different regions of the United States (example: Illinois Synod of the ELCA), whereas the word "synod" descends from a Greek word that means "walking together" and, in the case of WELS and LCMS, is applied to the entire church body and not just individual administrative units.
Beneath the president are numerous administrative divisions addressing various areas of ministry. Among these are ministerial education, world missions, home missions, parish services, and fiscal services.
Synod conventions are held biennially in odd-numbered years and consist of elected male lay members, ordained pastors and certified male teachers. Half of all delegates are to be lay members while the remaining half is divided between pastors and teachers. Synod conventions elect synodical leaders, and discuss and vote on synodical business. The WELS Synodical Council governs the church, when the church is not in convention.
The WELS is divided into 12 geographical districts in the United States and Canada, each headed by a district president elected in district conventions held during even-numbered years. District presidents serve terms of two years.
Wisconsin Lutheran College, a liberal arts college in Milwaukee, is affiliated with, though not run by, the WELS, and there are numerous area Lutheran high schools, Lutheran elementary schools, and early childhood education centers maintained by WELS congregations.
Northwestern Publishing House(
) is the official publishing house for the WELS. It is devoted to publishing Christian literature and WELS related religious materials, as well as several WELS periodicals.
Main WELS periodicals include:

In 1871 the Wisconsin Synod formally declared fellowship (in this context, an agreement recognizing doctrinal unity) with the Lutheran Church - Missouri Synod to form the Evangelical Lutheran Synodical Conference of North America, commonly called the "Synodical Conference." The Synodical Conference was later joined by the ELS in 1917. The fellowship union included full communion among members, the sharing of educational facilities, joint mission and benevolence work, and open pulpit between pastors of the different synods. This fellowship relationship would last for 90 years.
In 1893, two Wisconsin Synod missionaries began work in Arizona at Peridot and Old San Carlos among the Apache people. Congregations were soon established. Currently there are eight Wisconsin Synod congregations on the reservation. 
In 1917 the Wisconsin Synod joined with several sister synods in neighboring states, including the Minnesota Synod, the Michigan Lutheran Synod, and the Nebraska Synod, to become the Wisconsin Evangelical Lutheran Synod. By 1930, the merger and other factors had pushed the WELS to become a primarily English-speaking synod.
From 1926-29, a small group of persons and congregations were expelled or voluntarily left the WELS in an incident known as the "Protes'tant Controversy." They formed the Protes'tant Conference.
Doctrinal differences among the synods of the Synodical Conference, especially concerning the doctrine and practice of church fellowship, surfaced during the 1940s and '50s. Problems began when the LCMS began exploratory talks with leaders of the American Lutheran Church (ALC). The ALC differed on their doctrine of Predestination and therefore did not share doctrinal fellowship with the Synodical Conference. Since there had been no recent change on the ALC's doctrinal position, the LCMS was then charged by some within the Synodical Conference of changing its position on church fellowship. After years of continued talks, the ELS severed its fellowship relations with the LCMS in 1955 and withdrew from the Synodical Conference. Two years later the WELS publicly recognized the same doctrinal disagreements with the LCMS, but did not officially break fellowship with the LCMS until 1961. In this time period, the WELS instead decided to "admonish" the LCMS to return to its former doctrine and practice. Dissatisfaction over this decision led about 70 pastors and a similar number of congregations to leave the WELS and form the Church of the Lutheran Confession (CLC). Their chief complaint was that the WELS misapplied the principles of Christian fellowship by not breaking immediately with the Synodical Conference and the LCMS after it had publicly recognized doctrinal disagreements. To this day the CLC and the WELS remain at odds regarding this issue.
In 1993 the ELS and WELS, working with a number of other Lutheran synods around the world -- some of which had been founded through mission work by both synods -- founded a new fellowship organization which is the theological successor of the Synodical Conference: the Confessional Evangelical Lutheran Conference (CELC).
| Years of Service | President |
|---|---|
| 1850-1860 | Johannes Muehlhaeuser |
| 1860-1864 | John Bading |
| 1864-1865 | Gottlieb Rein |
| 1865-1867 | William Streissguth |
| 1867-1887 | John Bading |
| 1887-1908 | Phillip von Rohr |
| 1908-1933 | G.E. Bergemann |
| 1933-1953 | John Brenner |
| 1953-1979 | Oscar J. Naumann |
| 1979-1993 | Carl Mischke |
| 1993-2007 | Karl R. Gurgel |
| 2007-present | Mark Schroeder |
, while the ELCA has not enforced an official position, allowing members to embrace positions ranging from strict creationism to Theistic evolution.
There have recently been sharp divisions within the church over these issues, and a statement is expected during the 2009 Churchwide Assembly 
The WELS is in fellowship with the members of the Confessional Evangelical Lutheran Conference, all of which meet this requirement.