diff --git a/src/model/history.js b/src/model/history.js
index f8598ae..ecc7fcc 100644
--- a/src/model/history.js
+++ b/src/model/history.js
@@ -119,6 +119,15 @@ NetVis.prototype._constructHistory = function() {
 		}
 	};
 
+	self.history.prev = function() {
+		if (!self._selectedTimeInterval) {
+			return;
+		}
+		if (self._selectedTimeInterval.prev) {
+			self._selectedTimeInterval = self._selectedTimeInterval.prev;
+		}
+	};
+
 	// add default time margin moments
 	self.history.loadEvent({"tag":"end"},moment("3000-01-01"));
 	self.history.loadEvent({"tag":"start"},moment("1970-01-01"));