The number of peers has varied considerably with time. At the end of the Wars of the Roses, which killed many nobles and degraded or attainted many others, there were only 29 Lords Temporal. The Tudors doubled the number of peers, creating many but executing others and at the death of Elizabeth I there were 59.
Thereafter, the Peerage experienced a further swelling under the Stuarts and all subsequent monarchs. By the time of Queen Anne’s death there were 168 peers and, in 1712 alone, she was called upon to create 12 in one day in order to pass a government measure; more than Elizabeth I had created during a reign of nearly half a century.
Several peers were alarmed at the rapid increase in the size of the Peerage, fearing that their individual importance and power would decrease as the number of peers increased.
Therefore, in 1719, a bill was introduced in the House of Lords to place a limitation on the Crown’s power. It sought to permit no more than six new creations, and thereafter one new creation for each other title that became extinct. It did allow, however, the Crown to bestow titles on members of the Royal Family without any such limitation.
The Bill was rejected in its final stage in the Lords, but was passed when it was re-introduced in the following year. Nonetheless, the House of Commons rejected the bill 269 to 177.
George III was especially profuse with the creation of titles mostly because, unlike his Hanoverian forebears, he considered Great Britain his primary realm and took a very active role in its governance and therefore sought to obtain a majority in the House of Lords. During his 12 years as the king’s first minister, for example, Lord North had about 30 new peerages created. He was succeeded by William Pitt the Younger who created more than 140 new peerages in 17 years.
A restriction on the creation of peerages, but only in the Peerage of Ireland, was enacted under the Acts of Union 1800 that combined Ireland and Great Britain into the United Kingdom in 1801. New creations were restricted to a maximum of one new Irish peerage for every three existing Irish peerages that became extinct, excluding those held concurrently with an English or British peerage; only if the total number of Irish peers dropped below one hundred could the Sovereign create one new Irish peerage for each extinction.
Still, there remained no restrictions on creations in the Peerage of the United Kingdom. As such, the Peerage continued to swell through the 19th century and the lack of any limit allowed the 2nd Earl Grey to threaten a mass creation of Whig peers to pass the Reform Bill of 1832 if it was rejected by the House of Lords. This same threat was made to the House by the Liberals during the Constitutional Crisis of 1909-11, which led to the House of Lords voluntarily abolishing its veto and enshrining the primacy of the House of Commons.
New creations continued to increase as the 20th century wore on, as peerages were conferred less to honour the recipient as to give them a seat in the House, increasing the present administration’s influence over the upper chamber. However, after the passage of the Life Peerages Act 1958, the creation of hereditary peerages diminished. Only three have been created since 1964 and all in the premiership of Margaret Thatcher; the Viscount Whitelaw (extinct), the Viscount Tonypandy (extinct) and the Earl of Stockton.