The Articles of Confederation, the first constitution of the United States, had several weaknesses and strengths during its existence from 1777 to 1789.

Weaknesses:

1. Lack of Central Authority:  One of the most significant weaknesses was the absence of a strong central authority. The Articles established a weak central government with limited powers. It couldn't levy taxes, regulate commerce, or enforce laws effectively.

2. Financial Problems: The inability to tax meant that the federal government had financial difficulties. It relied on voluntary contributions from states, which often fell short. This resulted in unpaid debts and a struggling economy.

3. Inadequate Military: The central government couldn't maintain a standing army. It had to rely on state militias, making national defense challenging, as states often prioritized their own interests over the nation's security.

4. No Executive or Judiciary: The Articles didn't establish a separate executive branch or a national judiciary. There was no single leader to enforce laws or resolve disputes between states, leading to legal and political uncertainties.

5. Amendment Difficulty: Amending the Articles required unanimous approval from all 13 states, making it nearly impossible to adapt to changing circumstances or address weaknesses.

Strengths:

1. Preservation of Sovereignty: The Articles of Confederation sought to protect the sovereignty of individual states. This was important to many Americans who had just fought a war against what they saw as British tyranny.

2. Land Ordinance of 1785: The Articles established a process for organizing and admitting new states to the Union through the Land Ordinance of 1785. This encouraged westward expansion and the orderly settlement of territories.

3. Treaty of Paris (1783): The Articles facilitated the negotiation and signing of the Treaty of Paris, officially ending the Revolutionary War and recognizing the United States as an independent nation.

4. Northwest Ordinance of 1787: The Northwest Ordinance, enacted under the Articles, provided a blueprint for admitting new states to the Union and banning slavery in the Northwest Territory, emphasizing the importance of democratic principles in the expansion of the nation.

5. Early Steps Toward a Constitutional Convention: The weaknesses of the Articles eventually led to the Constitutional Convention of 1787, where the U.S. Constitution was drafted and adopted, creating a stronger federal government while preserving certain state powers.

In conclusion, the Articles of Confederation had significant weaknesses, including a lack of central authority, financial problems, and an inability to regulate trade or maintain a military. However, they also had strengths, such as preserving state sovereignty and providing a framework for westward expansion and the admission of new states. Ultimately, the weaknesses of the Articles highlighted the need for a more robust federal government, leading to the drafting and ratification of the U.S. Constitution.