A more thorough explanation:

Auxilium regis

Auxilium regis is a tax that is collected by the government for the use of the king or queen and for public services. This tax is usually granted by the parliament.

One example of auxilium regis is the tax that was collected in medieval England. The king would collect this tax to fund his military campaigns and to maintain his court. Another example is the tax that was collected in France during the reign of Louis XIV. This tax was used to fund the construction of the Palace of Versailles.

These examples illustrate how auxilium regis was used to fund the needs of the king or queen and to provide public services. The tax was collected from the people and used for the benefit of the entire kingdom.