How did the Latin alphabet create challenges for early writers of Romance languages?

When early scribes began writing in vernacular Romance languages, they found the Latin alphabet inadequate for representing the non-Latin sounds of their spoken languages. To address these limitations, they employed several strategies:1

• Letter Combinations: Scribes added the letter h to others to indicate new pronunciations, such as ch for /ch/ or /sh/ sounds. They also used combinations like nn, gn, nj, ll, gl, nh, and lh to represent palatal consonants.1
• Repurposing Letters: Existing letters were adapted for new sounds. For example, x was used for /sh/ or /z/ sounds in various dialects, while z was used in Italy for /ts/ and /dz/ sounds.1
• Distinguishing Vowels and Consonants: Scribes began to differentiate between i and j, and u and v, to separate vowel and consonant values.1
• Diacritics: To manage sounds not present in Latin, scribes eventually introduced diacritical marks, such as the tilde in Portuguese or the diaeresis to distinguish diphthongs from adjoining vowels.1

Over time, many languages shifted toward an "etymological" spelling style, which often created a disconnect between the written form and the evolving phonology of the spoken language.1