Question: When did the majority party in the House of Representatives gain control of the body which determines rules of the US House and US Senate?

Knowledge 1: Standing Rules of the United States Senate
The Standing Rules of the Senate are the parliamentary procedures adopted by the United States Senate that govern its procedure. The Senate's power to establish rules derives from Article One, Section 5 of the United States Constitution: ``Each House may determine the rules of its proceedings... '' [SEP] Knowledge 2: 110th United States Congress
The Democratic Party controlled a majority in both chambers for the first time since the end of the 103rd Congress in 1995. Although the Democrats held fewer than 50 Senate seats, they had an operational majority because the two independent senators caucused with the Democrats for organizational purposes. No Democratic - held seats had fallen to the Republican Party in the 2006 elections. Democrat Nancy Pelosi became the first woman Speaker of the House. The House also received the first Muslim (Keith Ellison) and Buddhist (Hank Johnson and Mazie Hirono) members of Congress. [SEP] Knowledge 3: Party leaders of the United States House of Representatives
Party leaders and whips of the United States House of Representatives, also known as floor leaders, are elected by their respective parties in a closed - door caucus by secret ballot. With the Republicans holding a majority of seats and the Democrats holding a minority, the current leaders are: Majority Leader Kevin McCarthy, Majority Whip Steve Scalise, Minority Leader Nancy Pelosi, and Minority Whip Steny Hoyer.
Knowledge 1: Standing Rules of the United States Senate
The Standing Rules of the Senate are the parliamentary procedures adopted by the United States Senate that govern its procedure. The Senate's power to establish rules derives from Article One, Section 5 of the United States Constitution: ``Each House may determine the rules of its proceedings... '' [SEP] Knowledge 2: 110th United States Congress
The Democratic Party controlled a majority in both chambers for the first time since the end of the 103rd Congress in 1995. Although the Democrats held fewer than 50 Senate seats, they had an operational majority because the two independent senators caucused with the Democrats for organizational purposes. No Democratic - held seats had fallen to the Republican Party in the 2006 elections. Democrat Nancy Pelosi became the first woman Speaker of the House. The House also received the first Muslim (Keith Ellison) and Buddhist (Hank Johnson and Mazie Hirono) members of Congress. [SEP] Knowledge 3: Party leaders of the United States House of Representatives
The current Minority Leader Nancy Pelosi, of the United States House of Representatives serves as floor leader of the opposition party, and is the counterpart to the Majority Leader. Unlike the Majority Leader, the Minority Leader is on the ballot for Speaker of the House during the convening of the Congress. If the Minority Leader's party takes control of the House, and the party officers are all re-elected to their seats, the Minority Leader is usually the party's top choice for Speaker for the next Congress, while the Minority Whip is typically in line to become Majority Leader. The Minority Leader usually meets with the Majority Leader and the Speaker to discuss agreements on controversial issues.
Knowledge 1: Standing Rules of the United States Senate
The Standing Rules of the Senate are the parliamentary procedures adopted by the United States Senate that govern its procedure. The Senate's power to establish rules derives from Article One, Section 5 of the United States Constitution: ``Each House may determine the rules of its proceedings... '' [SEP] Knowledge 2: Party leaders of the United States House of Representatives
Party leaders and whips of the United States House of Representatives, also known as floor leaders, are elected by their respective parties in a closed - door caucus by secret ballot. With the Republicans holding a majority of seats and the Democrats holding a minority, the current leaders are: Majority Leader Kevin McCarthy, Majority Whip Steve Scalise, Minority Leader Nancy Pelosi, and Minority Whip Steny Hoyer. [SEP] Knowledge 3: 2014 United States Senate elections
The Republicans regained the majority of the Senate in the 114th Congress, which started in January 2015; the Republicans had not controlled the Senate since January 2007. They had needed a net gain of at least six seats to obtain a majority. They held all of their seats, and gained nine Democratic - held seats. Republicans defeated five Democratic incumbents:

Answer: January 2015