This is the signiture of Bartolomeo Lelii at the end of his legal document

The handwriting used in manuscripts and documents were subject to greater discipline and more rigid rules and hierarchies than modern personal handwriting, for in early book production such professional or semi-professional handwriting had to serve many of the functions of modern print.[1]

In each different government department they all had their own unique and distinctive scripts. Seldom was the same grade of script used for, say, a liturgical manuscript and a legal document. 

In Roman antiquity, writing was done with a reed pen. However, throughout the medieval era a quill was evidently the more usual instrument.[2]

There were many ways to make a writing instrument, the business end of a strong feather, such as a pinion of a goose, was first buried in hot sand to change the structure and make it stronger and less brittle. Usually the flights of the feather were removed, making it easier to handle but less photogenic and romantic. The nib was cut to shape with a small knife. The pen was then ready for use. The shaping procedure was regularly repeated to sharpen the nib during use.[3]

The cut and thickness of the pen nib alters the appearance and degree of formality of a script.[4] Writing materials generally influenced the development of letter forms.