diff --git a/cider-repl-history.el b/cider-repl-history.el
index e5044bf6e..a109fc7d8 100644
--- a/cider-repl-history.el
+++ b/cider-repl-history.el
@@ -220,15 +220,6 @@ call `cider-repl-history' again.")
 (defvar cider-repl-history-previous-overlay nil
   "Previous overlay within *cider-repl-history* buffer.")
 
-
-(defun cider-repl-history-get-history ()
-  "Function to retrieve history from the REPL buffer."
-  (if cider-repl-history-repl-buffer
-      (buffer-local-value
-       'cider-repl-input-history
-       cider-repl-history-repl-buffer)
-    (error "Variable `cider-repl-history-repl-buffer' not bound to a buffer")))
-
 (defun cider-repl-history-resize-window ()
   "Resize the *cider-repl-history* window if needed.
 Controlled by variable `cider-repl-history-resize-window'."
@@ -597,7 +588,7 @@ HISTORY-BUF is the history, and optional arg REGEXP is a filter."
                            (<= cider-repl-history-maximum-display-length 3))
                       4
                     cider-repl-history-maximum-display-length))
-                 (cider-command-history (cider-repl-history-get-history))
+                 (cider-command-history cider-repl-input-history)
                  (items (mapcar
                          (if cider-repl-history-text-properties
                              #'copy-sequence
diff --git a/cider-repl.el b/cider-repl.el
index 173b0dc54..c82fba092 100644
--- a/cider-repl.el
+++ b/cider-repl.el
@@ -165,6 +165,9 @@ See also `cider-repl-eval-init-code'."
   :type '(list string)
   :package-version '(cider . "0.21.0"))
 
+(defvar cider-repl-input-history '()
+  "History list of strings read from the REPL buffer.")
+
 (defcustom cider-repl-display-help-banner t
   "When non-nil a bit of help text will be displayed on REPL start."
   :type 'boolean
@@ -194,12 +197,6 @@ CIDER 1.7."
 This property value must be unique to avoid having adjacent inputs be
 joined together.")
 
-(defvar-local cider-repl-input-history '()
-  "History list of strings read from the REPL buffer.")
-
-(defvar-local cider-repl-input-history-items-added 0
-  "Variable counting the items added in the current session.")
-
 (defvar-local cider-repl-output-start nil
   "Marker for the start of output.
 Currently its only purpose is to facilitate `cider-repl-clear-buffer'.")
@@ -1473,8 +1470,7 @@ WIN, BUFFER and POS are the window, buffer and point under mouse position."
 Empty strings and duplicates are ignored."
   (unless (or (equal string "")
               (equal string (car cider-repl-input-history)))
-    (push string cider-repl-input-history)
-    (cl-incf cider-repl-input-history-items-added)))
+    (push string cider-repl-input-history)))
 
 (defun cider-repl-delete-current-input ()
   "Delete all text after the prompt."
@@ -1629,11 +1625,8 @@ The value of `cider-repl-input-history' is set by this function."
   "Write history to FILENAME.
 Currently coding system for writing the contents is hardwired to
 utf-8-unix."
-  (let* ((mhist (cider-repl--histories-merge cider-repl-input-history
-                                             cider-repl-input-history-items-added
-                                             (cider-repl--history-read filename)))
-         ;; newest items are at the beginning of the list, thus 0
-         (hist (cl-subseq mhist 0 (min (length mhist) cider-repl-history-size))))
+  (let* ((end (min (length cider-repl-input-history) cider-repl-history-size))
+         (hist (cl-subseq cider-repl-input-history 0 end)))
     (unless (file-writable-p filename)
       (error (format "History file not writable: %s" filename)))
     (let ((print-length nil) (print-level nil))
@@ -1658,16 +1651,6 @@ This function is meant to be used in hooks to avoid lambda
 constructs."
   (cider-repl-history-save cider-repl-history-file))
 
-;; SLIME has different semantics and will not save any duplicates.
-;; we keep track of how many items were added to the history in the
-;; current session in `cider-repl--add-to-input-history' and merge only the
-;; new items with the current history found in the file, which may
-;; have been changed in the meantime by another session.
-(defun cider-repl--histories-merge (session-hist n-added-items file-hist)
-  "Merge histories from SESSION-HIST adding N-ADDED-ITEMS into FILE-HIST."
-  (append (cl-subseq session-hist 0 n-added-items)
-          file-hist))
-
 
 ;;; REPL shortcuts
 (defcustom cider-repl-shortcut-dispatch-char ?\,