diff --git a/game-app/game-core/src/main/java/games/strategy/engine/history/History.java b/game-app/game-core/src/main/java/games/strategy/engine/history/History.java
index 9958a9a2d71..6d146233c87 100644
--- a/game-app/game-core/src/main/java/games/strategy/engine/history/History.java
+++ b/game-app/game-core/src/main/java/games/strategy/engine/history/History.java
@@ -31,8 +31,10 @@ public class History extends DefaultTreeModel {
   private final HistoryWriter writer = new HistoryWriter(this);
   private final List<Change> changes = new ArrayList<>();
   private final GameData gameData;
-  private HistoryNode currentNode;
-  private HistoryPanel panel = null;
+  private HistoryPanel panel;
+  // Index at which point we are in history. Only valid if seekingEnabled is true.
+  private int nextChangeIndex;
+  private boolean seekingEnabled = false;
 
   public History(final GameData data) {
     super(new RootHistoryNode("Game History"));
@@ -49,8 +51,15 @@ public HistoryWriter getHistoryWriter() {
     return writer;
   }
 
-  public void setTreePanel(final HistoryPanel panel) {
+  public HistoryNode enableSeeking(final HistoryPanel panel) {
+    Preconditions.checkNotNull(panel);
+    Preconditions.checkState(!seekingEnabled);
     this.panel = panel;
+    nextChangeIndex = changes.size();
+    seekingEnabled = true;
+    HistoryNode lastNode = getLastNode();
+    gotoNode(lastNode);
+    return lastNode;
   }
 
   public void goToEnd() {
@@ -95,37 +104,25 @@ private int getLastChange(final HistoryNode node) {
     return lastChangeIndex;
   }
 
-  public Change getDelta(final HistoryNode start, final HistoryNode end) {
-    assertCorrectThread();
-    final int firstChange = getLastChange(start);
-    final int lastChange = getLastChange(end);
-    if (firstChange == lastChange) {
-      return null;
-    }
+  private Change getDeltaTo(int changeIndex) {
     final List<Change> deltaChanges =
-        changes.subList(Math.min(firstChange, lastChange), Math.max(firstChange, lastChange));
+        changes.subList(
+            Math.min(nextChangeIndex, changeIndex), Math.max(nextChangeIndex, changeIndex));
     final Change compositeChange = new CompositeChange(deltaChanges);
-    return (lastChange >= firstChange) ? compositeChange : compositeChange.invert();
+    return (changeIndex >= nextChangeIndex) ? compositeChange : compositeChange.invert();
   }
 
   /** Changes the game state to reflect the historical state at {@code node}. */
   public synchronized void gotoNode(final HistoryNode node) {
-    // Setting node to null causes problems, because we'll restore the state to the start, but then
-    // next gotoNode() call will reset currentNode to getLastNode() causing an invalid delta.
-    Preconditions.checkNotNull(node);
     assertCorrectThread();
-    gameData.acquireWriteLock();
-    try {
-      if (currentNode == null) {
-        currentNode = getLastNode();
-      }
-      final Change dataChange = getDelta(currentNode, node);
-      currentNode = node;
-      if (dataChange != null) {
-        gameData.performChange(dataChange);
+    Preconditions.checkNotNull(node);
+    Preconditions.checkState(seekingEnabled);
+    try (GameData.Unlocker ignored = gameData.acquireWriteLock()) {
+      final int nodeChangeIndex = getLastChange(node);
+      if (nodeChangeIndex != nextChangeIndex) {
+        gameData.performChange(getDeltaTo(nodeChangeIndex));
+        nextChangeIndex = nodeChangeIndex;
       }
-    } finally {
-      gameData.releaseWriteLock();
     }
   }
 
@@ -136,8 +133,7 @@ public synchronized void gotoNode(final HistoryNode node) {
   public synchronized void removeAllHistoryAfterNode(final HistoryNode removeAfterNode) {
     gotoNode(removeAfterNode);
     assertCorrectThread();
-    gameData.acquireWriteLock();
-    try {
+    try (GameData.Unlocker ignored = gameData.acquireWriteLock()) {
       final int lastChange = getLastChange(removeAfterNode) + 1;
       while (changes.size() > lastChange) {
         changes.remove(lastChange);
@@ -160,20 +156,16 @@ public synchronized void removeAllHistoryAfterNode(final HistoryNode removeAfter
         }
       }
       while (!nodesToRemove.isEmpty()) {
-        this.removeNodeFromParent(nodesToRemove.remove(0));
+        removeNodeFromParent(nodesToRemove.remove(0));
       }
-    } finally {
-      gameData.releaseWriteLock();
     }
   }
 
   synchronized void changeAdded(final Change change) {
     changes.add(change);
-    if (currentNode == null) {
-      return;
-    }
-    if (currentNode == getLastNode()) {
+    if (seekingEnabled && nextChangeIndex == changes.size()) {
       gameData.performChange(change);
+      nextChangeIndex = changes.size();
     }
   }
 
diff --git a/game-app/game-core/src/main/java/games/strategy/triplea/ui/history/HistoryPanel.java b/game-app/game-core/src/main/java/games/strategy/triplea/ui/history/HistoryPanel.java
index 40958512073..f51c36f3755 100644
--- a/game-app/game-core/src/main/java/games/strategy/triplea/ui/history/HistoryPanel.java
+++ b/game-app/game-core/src/main/java/games/strategy/triplea/ui/history/HistoryPanel.java
@@ -80,7 +80,6 @@ public void mouseEntered(final MouseEvent e) {
     tree = new JTree(this.data.getHistory());
     // Register the tree with the tooltip manager to make the tooltips we set work.
     ToolTipManager.sharedInstance().registerComponent(tree);
-    this.data.getHistory().setTreePanel(this);
     tree.expandRow(0);
     this.popup = popup;
     tree.add(this.popup);
@@ -112,12 +111,10 @@ public void popupMenuWillBecomeVisible(final PopupMenuEvent pme) {}
     scroll.setBorder(null);
     scroll.setViewportBorder(null);
     add(scroll, BorderLayout.CENTER);
+    HistoryNode node = data.getHistory().enableSeeking(this);
     tree.setEditable(false);
-    final HistoryNode node = this.data.getHistory().getLastNode();
-    this.data.getHistory().gotoNode(node);
     tree.expandPath(new TreePath(node.getPath()));
     tree.setSelectionPath(new TreePath(node.getPath()));
-    currentPopupNode = null;
     final JButton previousButton = new JButton("<-Back");
     previousButton.addMouseListener(mouseFocusListener);
     previousButton.addActionListener(e -> previous());