diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 092a355071..65d500b28e 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -218,7 +218,7 @@ leave out at most one of A and B, in which case it defaults to HEAD.
 	merge base of `<upstream>` and `<branch>`. Running
 	`git rebase --keep-base <upstream> <branch>` is equivalent to
 	running
-	`git rebase --reapply-cherry-picks --onto <upstream>...<branch> <upstream> <branch>`.
+	`git rebase --reapply-cherry-picks --no-fork-point --onto <upstream>...<branch> <upstream> <branch>`.
 +
 This option is useful in the case where one is developing a feature on
 top of an upstream branch. While the feature is being worked on, the
@@ -452,9 +452,9 @@ When `--fork-point` is active, 'fork_point' will be used instead of
 <branch>` command (see linkgit:git-merge-base[1]).  If 'fork_point'
 ends up being empty, the `<upstream>` will be used as a fallback.
 +
-If `<upstream>` is given on the command line, then the default is
-`--no-fork-point`, otherwise the default is `--fork-point`. See also
-`rebase.forkpoint` in linkgit:git-config[1].
+If `<upstream>` or `--keep-base` is given on the command line, then
+the default is `--no-fork-point`, otherwise the default is
+`--fork-point`. See also `rebase.forkpoint` in linkgit:git-config[1].
 +
 If your branch was based on `<upstream>` but `<upstream>` was rewound and
 your branch contains commits which were dropped, this option can be used
diff --git a/builtin/rebase.c b/builtin/rebase.c
index 0287f3e817..ef520f66fb 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -1230,6 +1230,12 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 			die(_("options '%s' and '%s' cannot be used together"), "--keep-base", "--onto");
 		if (options.root)
 			die(_("options '%s' and '%s' cannot be used together"), "--keep-base", "--root");
+		/*
+		 * --keep-base defaults to --no-fork-point to keep the
+		 * base the same.
+		 */
+		if (options.fork_point < 0)
+			options.fork_point = 0;
 	}
 	/*
 	 * --keep-base defaults to --reapply-cherry-picks to avoid losing
diff --git a/t/t3431-rebase-fork-point.sh b/t/t3431-rebase-fork-point.sh
index 1d0b15380e..70e8136356 100755
--- a/t/t3431-rebase-fork-point.sh
+++ b/t/t3431-rebase-fork-point.sh
@@ -50,7 +50,7 @@ test_rebase () {
 
 test_rebase 'G F E D B A'
 test_rebase 'G F D B A' --onto D
-test_rebase 'G F B A' --keep-base
+test_rebase 'G F C B A' --keep-base
 test_rebase 'G F C E D B A' --no-fork-point
 test_rebase 'G F C D B A' --no-fork-point --onto D
 test_rebase 'G F C B A' --no-fork-point --keep-base