The Virginia Plan was a proposal put forward at the Philadelphia Convention held in 1787 to improve the Articles of Confederation that the United States had been operating under since it achieved independence from Britain. Many of the ideas in the plan were incorporated into what later became the Constitution of the United States. There are many high-quality facsimiles of this document online for people who are interested in viewing it for themselves.
The Philadelphia Convention was originally intended to revise the Articles of Confederation to address perceived failings with the government of the United States. Some attendees intended from the outset to actually devise a new system of government, however, rather than trying to fix the existing one. The Virginia Plan was a reflection of the beliefs of the delegates from Virginia who wanted to develop an entirely new government. It was drafted by James Madison.
One of the most notable inclusions in the Virginia Plan was a suggestion that the government be split into judicial, executive, and legislative branches, with checks and balances to keep the distribution of power stable. In addition, the plan proposed having two house of legislature rather than one, and advocated for the use of proportional representation. This meant that rather than giving each state the same number of representatives, representatives should be distributed by population or wealth in their home state. Later, the decision was made to have one house with a fixed number of legislators and one with numbers determined by proportional representation.
This proposal is also known as the Randolph Plan or Large-State Plan. The Virginia Plan incorporated many ideas from larger states involved in the Convention and smaller states retaliated with the New Jersey Plan. The New Jersey Plan included proposals to rework the Articles of Confederation rather than to develop a new framework for American government. Using many ideas from the Virginia Plan, the Convention attendees also made some compromises, including the infamous three-fifths compromise used for counting the slave population.
Although the Virginia plan was not adopted in full, many of the ideas it contained were integrated into the new government of the United States, and it had a profound impact on the shaping of the Constitution. James Madison is sometimes referred to as one of the "Fathers of the Constitution" because of his role in the Convention and his work on the Virginia Plan.