J'ai écrit me semble-t-il qu'ils étaient en tenue de séminaristes romains, il peut bien y avoir des africains dans la même tenue, sans pour autant qu'ils soient chinois.
Quelques précisions sur les tenues tirées du site WDTPS, pour les anglophones, n'ayant pas le temps de traduire ce soir. Bonne et sainte nuit à tous.
" Consulting the 1900 Handbook to Christian and Ecclesiatical Rome by Tuker and Malleson and an old edition of Georgina Masson's classic Companion Guide to Rome we find the following descriptions of the seminarian dress of yore:
Seminary of the Diocese of Rome Purple Cassock and soprana with pendant strings and no sash.
Pontificio Provincale Pio Black cassock, violet sash, a full cloak
Vatican Seminary Dark purple cassock with cromson bindings and buttons, one crimson string decorated with the papal arms, buckle shoes
Capranica College Black cassock, black soprana of shiny cloth, stings, no sash, shoes with silver buckles
Propaganda Fide Black double breasted cassock, red pipings and buttons, scarlet sash and strings (photo at left)

Germanic College Scarlet Cassock, black sash, scarlet soprana with pendant strings (Masson notes that they had the nickname 'gamberi cotti' or 'boiled lobsters' and that their distinctive dress was imposed due to their reputation for uproarious behaviour)
Greek College Blue cassock, red sash and pipings, blue soprana with strings - out of doors: a black soprana with wide sleeves
English College Black cassock and soprana, black strings and no sash

Scots College Purple cassock with crimson sash, buttons and pipings. Black soprana with pendant strings (photo at left)

Irish College Black cassock with red piping, no sash, black soprana and strings
French College The first college to abandon collegiate dress for the priest's cassock, no sash (évidemment !)
Lombard College Black cassock, violet sash, soprana and strings
Seminary of SS. Peter and Paul Priest's dress with a black sash
Belgian College Priest's dress with a black sash edged with red
North American College Double-breasted black cassock, blue pipings and buttons, crimson sash, pendant strings
South American College Black cassock with blue edgings, blue sash, black soprana and strings
Maronite College Black cassock, soprana and strings
Bohemian College Black cassock, maroon sash edged with yellow
Armenian College Black cassock with red pipings, out of doors: black coat with wide sleeves
College of St Boniface Black cassock with yellow pipings, black soprana with black pendant srings lined with red
Polish College Black cassock and soprana with green sash
Spanish College Black cassock with blue sash, round black cape with vertical blue pipings
Candadian College Priest's dress and no sash
Ruthenian College Blue cassock, soprana with strings, orange sash..."