diff --git a/src/config/cli.rs b/src/config/cli.rs
index 52fbfa1..dc72f3a 100644
--- a/src/config/cli.rs
+++ b/src/config/cli.rs
@@ -81,7 +81,7 @@ pub fn build_cli() -> Command {
              2018-03-04|2018-03-04 12:34:56|2018-03-04T12:34: Absolute ISO date\n  \
              123456789:                                       Absolute unix timestamp\n  \
              1 year, 2 months|10d:                            Relative date\n  \
-             1c|2 commands                                    Emerge command";
+             1c|2 commands|c                                  Nth emerge command";
     let from = Arg::new("from").short('f')
                                .long("from")
                                .value_name("date")
@@ -95,7 +95,7 @@ pub fn build_cli() -> Command {
              2018-03-04|2018-03-04 12:34:56|2018-03-04T12:34: Absolute ISO date\n  \
              123456789:                                       Absolute unix timestamp\n  \
              1 year, 2 months|10d:                            Relative date\n  \
-             1c|2 commands                                    Emerge command";
+             1c|2 commands|c                                  Nth-last emerge command";
     let to = Arg::new("to").short('t')
                            .long("to")
                            .value_name("date")
diff --git a/src/datetime.rs b/src/datetime.rs
index 214898e..77b17e7 100644
--- a/src/datetime.rs
+++ b/src/datetime.rs
@@ -111,15 +111,14 @@ impl ArgParse<String, UtcOffset> for TimeBound {
     }
 }
 
-/// Parse a command index
+/// Parse a command index (parse as 1-based, return as 0-based)
 fn parse_command_num(s: &str) -> Result<usize, Error> {
     use atoi::FromRadix10;
-    match usize::from_radix_10(s.as_bytes()) {
-        (num, pos) if pos != 0 => match s[pos..].trim() {
-            "c" | "command" | "commands" => Ok(num),
-            _ => bail!("bad span {:?}", &s[pos..]),
-        },
-        _ => bail!("not a number"),
+    let (num, pos) = usize::from_radix_10(s.as_bytes());
+    match s[pos..].trim() {
+        "c" | "command" | "commands" if num > 0 => Ok(num - 1),
+        "c" | "command" if pos == 0 => Ok(0),
+        _ => bail!("bad span {:?}", &s[pos..]),
     }
 }
 
@@ -371,6 +370,19 @@ mod test {
         assert!(parse_date("a while ago", tz_utc).is_err());
     }
 
+    #[test]
+    fn command_num() {
+        assert_eq!(parse_command_num("1c").unwrap(), 0);
+        assert_eq!(parse_command_num("5c").unwrap(), 4);
+        assert_eq!(parse_command_num("c").unwrap(), 0);
+        assert_eq!(parse_command_num("1 commands ").unwrap(), 0);
+        assert!(parse_command_num("").is_err());
+        assert!(parse_command_num("0c").is_err());
+        assert!(parse_command_num("0").is_err());
+        assert!(parse_command_num("1cool").is_err());
+        assert!(parse_command_num("-1c").is_err());
+    }
+
     #[test]
     fn timespan_next_() {
         for t in [// input             year       month      week       day