The National Union Convention (also known as the Loyalist Convention, the Southern Loyalist Convention, the National Loyalists' Loyal Union Convention, or the Arm-In-Arm Convention) was held on August 14, 15, and 16 1866, in Philadelphia, Pennsylvania.
The convention was called in advance of the mid-year elections of 1866 in an attempt to help President Johnson, who was under heavy fire from both Radical Republicans and more moderate Republicans. Johnson's friends tried to rally support for the lenient, pro-South Reconstruction policies of President Andrew Johnson. The goal of creating a new political party was not realized.
Delegates gathered at a hastily built temporary structure that was designed to accommodate the several thousand people expected to attend. Formally called "the Wigwam", this immense edifice was located on Girard Avenue between 19th and 20th Streets, across from Philadelphia's Girard College.
About 7,000 prominent politicians and activists attended the convention. At its opening, representatives from Massachusetts (General Darius Nash Couch) and South Carolina (Governor James Lawrence Orr) paraded arm-in-arm to symbolize national reconciliation and social equity. The convention was called to order by U.S. Postmaster General Alexander Randall. General (and former New York Governor and Senator) John Adams Dix served as the temporary chairman and Wisconsin Senator James R. Doolittle served as permanent convention president.
In the end, the convention was not successful in unifying the country behind President Johnson. He then launched a speaking tour (known as the "Swing Around the Circle") hoping to regain public and political support. On this speaking tour, Johnson at times attacked his Republican opponents with crude and abusive language and on several occasions appeared to have had too much to drink. Ultimately, the tour was a disaster for Johnson, emboldening the Congress to override him and to impeach him in 1868.