The diework of this piece strongly indicates it to be a 19th or perhaps early 20th century medal, struck in one of the "white metal" alloys widely used in that era.
The
IHS with cross is unquestionably the Christogram or monogram (sometimes rendered as
JHS ) widely used by Christians, and especially Roman Catholics, for centuries:
http://www.newadvent.org/cathen/07649a.htm
The all-seeing eye is symbolic of God as well, although its usage is more common among fraternal than religious orders.
That it was issued as a religious commemorative medal is indicated by the legend
Zum Andenken an die heilige Mission, German for, "To the Memory of the Holy Mission." While this suggests that it was struck in, or for distribution in, Germany, it might also have come from one of the other German-speaking nations: Austria, Switzerland, Luxembourg, or Liechtenstein.
Interestingly, the same text appears as the title of a mid 19th century lithograph of a Jesuit mission in Karlsruhe, Germany.