Re: Eastern cz sz

>> I have a question about cz sz in the eastern european
>> writings : When did that started ?
>
> I believe that the digraphs <cz> for [c^] and <sz> for [S]
> are specifically Polish. I've seen them in onomastic
> sources by the later 14th century.

In Old Czech, there were two systems:
older zz = younger s = modern s
older ss = younger ss = modern s^
older z = younger z = modern z
older s = younger z(^)= modern z^
older cz = younger cz = modern c
older chz = younger cz(^) = modern c^
older rs = younger rz(^) = modern r^

P.A.