in principle, Si can be positioned as more of a full-featured "sport trim" of honda civic in USDM and for Japanese and European markets, Civic Type R was introduced as the "high-performance variant" of the honda civic.
Si's (sport injection) debut in US market came in the form of 1985 CRX Si and then a distinct Si was added into Civic hatchback for the following years ('87?) . Thus for Civic Si there have been 8-time iterations from 3g Civic to current 10g civic, actually. Since Si is primarily referred to as a sporty trim of civic, we name it along with civic generations, in general.
regarding civic type R, The first Civic to receive the Type R badge was adopted in 1997, as the EK9. And beside 1g and part of 3g civic type R (only 4-door, FD2) being assembled in Japan, all were/are made in England.