diff --git a/src/history/file_backed.rs b/src/history/file_backed.rs
index 28b437f7..72e521cf 100644
--- a/src/history/file_backed.rs
+++ b/src/history/file_backed.rs
@@ -291,7 +291,7 @@ impl FileBackedHistory {
             panic!("History capacity too large to be addressed safely");
         }
         FileBackedHistory {
-            capacity,
+            capacity: if capacity != 0 { capacity } else { 1 },
             entries: VecDeque::new(),
             file: None,
             len_on_disk: 0,