diff --git a/R/bs-theme-preset-bootswatch.R b/R/bs-theme-preset-bootswatch.R
index a670ad6eb..f7a9e76a0 100644
--- a/R/bs-theme-preset-bootswatch.R
+++ b/R/bs-theme-preset-bootswatch.R
@@ -96,9 +96,14 @@ bootswatch_bundle <- function(bootswatch, version) {
         # Use local fonts (this path is relative to the bootstrap HTML dependency dir)
         '$web-font-path: "font.css" !default;',
         bootswatch_sass_file(bootswatch, "variables", version),
-        # Unless we change navbarPage()'s markup, BS4+ will likely want BS3 compatibility
+        # BS4 navbars are matched with BS3 for compatibility
         switch_version(
-          version, three = "", default = bs3compat_navbar_defaults(bootswatch)
+          version, 
+          three = "",
+          four = bs3compat_navbar_defaults(bootswatch),
+          # BS5 uses more neutral defaults (navbar that flips in light/dark mode)
+          # or requires a bit more user input
+          default = list()
         )
       ),
       rules = list(
diff --git a/inst/bs3compat/_navbar_compat.scss b/inst/bs3compat/_navbar_compat.scss
index 9322d1863..bad66a8cd 100644
--- a/inst/bs3compat/_navbar_compat.scss
+++ b/inst/bs3compat/_navbar_compat.scss
@@ -72,42 +72,58 @@ ul.nav.navbar-nav {
   }
 }
 
+:root {
+  --bslib-navbar-light-bg: var(--bslib-navbar-default-bg, var(--#{$prefix}light));
+  --bslib-navbar-dark-bg: var(--bslib-navbar-inverse-bg, var(--#{$prefix}black));
+}
+
+@mixin navbar-background-dark($important: false) {
+  background-color: var(--bslib-navbar-dark-bg) if($important, !important, null);
+}
+
+@mixin navbar-background-light($important: false) {
+  background-color: var(--bslib-navbar-light-bg) if($important, !important, null);
+}
 
 .navbar {
 
   // Defaults to null (and in that case, we don't want to define the CSS var)
   @if $navbar-light-bg {
-    --bslib-navbar-default-bg: #{$navbar-light-bg};
+    --bslib-navbar-light-bg: #{$navbar-light-bg};
   }
   @if $navbar-dark-bg {
-    --bslib-navbar-inverse-bg: #{$navbar-dark-bg};
-  }
-
-  // BS3 .navbar-default -> BS4 .navbar-light
-  &.navbar-default {
-    // Sets a variety of fg colors which are configurable via $navbar-light-* options
-    @extend .navbar-light;
-    background-color: var(--bslib-navbar-default-bg, var(--#{$prefix}light)) !important;
+    --bslib-navbar-dark-bg: #{$navbar-dark-bg};
   }
 
-  // BS3 .navbar-inverse -> BS4 .navbar-dark
-  &.navbar-inverse {
-    // Sets a variety of fg colors which are configurable via $navbar-dark-* options
-    @extend .navbar-dark;
-    background-color: var(--bslib-navbar-inverse-bg, var(--#{$prefix}dark)) !important;
-    // For BS5+ lean on emphasis-color
-    --bs-emphasis-color: white;
-    --bs-emphasis-color-rgb: 255, 255, 255;
+  @if $bootstrap-version < 5 {
+    // BS3 .navbar-default -> BS4 .navbar-light
+    &.navbar-default {
+      // Sets a variety of fg colors which are configurable via $navbar-light-* options
+      @extend .navbar-light;
+      @include navbar-background-light($important: true);
+    }
+  
+    // BS3 .navbar-inverse -> BS4 .navbar-dark
+    &.navbar-inverse {
+      // Sets a variety of fg colors which are configurable via $navbar-dark-* options
+      @extend .navbar-dark;
+      @include navbar-background-dark($important: true);
+    }
   }
 }
 
-$enable-dark-mode: false !default;
-@if $enable-dark-mode {
-  @include color-mode(dark) {
-    .navbar.navbar-default {
-      background-color: var(--bslib-navbar-default-bg, var(--#{$prefix}dark)) !important;
-    }
+@if $bootstrap-version >= 5 {
+  .navbar {
+    background-color: $navbar-bg;
   }
+  
+  [data-bs-theme="dark"] :where(.navbar) { @include navbar-background-dark(); }
+  [data-bs-theme="light"] :where(.navbar), :where(.navbar) { @include navbar-background-light(); }
+  
+  // These are defined *after* the above rules because we want the local version
+  // to win without having to resort to specificity tricks.
+  :where(.navbar)[data-bs-theme="dark"] { @include navbar-background-dark(); }
+  :where(.navbar)[data-bs-theme="light"] { @include navbar-background-light(); }
 }
 
 // Implement bs3 navbar toggler; used in Rmd websites, i.e.
diff --git a/inst/builtin/bs5/shiny/_rules.scss b/inst/builtin/bs5/shiny/_rules.scss
index 64f3316ca..64f022e9e 100644
--- a/inst/builtin/bs5/shiny/_rules.scss
+++ b/inst/builtin/bs5/shiny/_rules.scss
@@ -173,14 +173,15 @@ $bslib-checkbox-radio-margin-right: 0.35em !default;
     background-color: var(--bslib-dashboard-main-bg);
   }
 
+  .navbar {
+    // Add border-bottom for general navbars (primarily in non-bslib contexts)
+    border-bottom: $card-border-width solid $card-border-color;
+  }
+
   .bslib-page-navbar, .bslib-page-dashboard {
-    > .navbar {
-      @if not $navbar-light-bg and not $navbar-bg {
-        --bslib-navbar-default-bg: var(--#{$prefix}body-bg);
-      }
-      @if not $navbar-dark-bg and not $navbar-bg {
-        --bslib-navbar-inverse-bg: var(--#{$prefix}body-color);
-      }
+    // Inside bslib we only add the border on the top-level navbar
+    .navbar {
+      border-bottom: none;
     }
 
     > .navbar + div {
diff --git a/inst/builtin/bs5/shiny/_variables.scss b/inst/builtin/bs5/shiny/_variables.scss
index 71d44d4d4..c7d45a002 100644
--- a/inst/builtin/bs5/shiny/_variables.scss
+++ b/inst/builtin/bs5/shiny/_variables.scss
@@ -148,6 +148,21 @@ $bslib-sidebar-fg: null !default;
   $bslib-sidebar-fg: color-contrast($bslib-sidebar-bg);
 }
 
+// From inst/lib/bs5/scss/_variables.scss
+// Repeated here so that we can set navbar light/dark to `--bs-body-bg`
+$navbar-bg:       null !default; // Background color for any navbarPage()
+$navbar-light-bg: $navbar-bg !default; // Background color for navbarPage(inverse = FALSE)
+$navbar-dark-bg:  $navbar-bg !default; // Background color for navbarPage(inverse = TRUE)
+
+@if $bslib-dashboard-design and $navbar-bg == null {
+  @if $navbar-light-bg == null {
+    $navbar-light-bg: var(--#{$prefix}body-bg);
+  }
+  @if $navbar-dark-bg == null {
+    $navbar-dark-bg: var(--#{$prefix}body-bg);
+  }
+}
+
 $border-color-translucent: if($bslib-dashboard-design, rgba(40, 70, 94, 0.1), null) !default;
 $border-color-translucent-dark: if($bslib-dashboard-design, rgba(255, 255, 255, 0.1), null) !default;
 
diff --git a/inst/lib/bs5/scss/_navbar.scss b/inst/lib/bs5/scss/_navbar.scss
index 988bbe09c..ec497278c 100644
--- a/inst/lib/bs5/scss/_navbar.scss
+++ b/inst/lib/bs5/scss/_navbar.scss
@@ -3,7 +3,8 @@
 // Provide a static navbar from which we expand to create full-width, fixed, and
 // other navbar variations.
 
-.navbar {
+.navbar,
+:where([data-bs-theme="light"]) .navbar { // bslib-patched: explicitly set navbar props in light mode regions
   // scss-docs-start navbar-css-vars
   --#{$prefix}navbar-padding-x: #{if($navbar-padding-x == null, 0, $navbar-padding-x)};
   --#{$prefix}navbar-padding-y: #{$navbar-padding-y};
@@ -26,7 +27,9 @@
   --#{$prefix}navbar-toggler-focus-width: #{$navbar-toggler-focus-width};
   --#{$prefix}navbar-toggler-transition: #{$navbar-toggler-transition};
   // scss-docs-end navbar-css-vars
+}
 
+.navbar {
   position: relative;
   display: flex;
   display: -webkit-flex;
@@ -296,6 +299,7 @@
 }
 
 .navbar-dark,
+:where([data-bs-theme="dark"]) .navbar, // bslib-patched: dark mode inside dark regions
 .navbar[data-bs-theme="dark"] {
   // scss-docs-start navbar-dark-css-vars
   --#{$prefix}navbar-color: #{$navbar-dark-color};
@@ -309,10 +313,32 @@
   // scss-docs-end navbar-dark-css-vars
 }
 
+:where(.navbar[data-bs-theme="dark"] .navbar-toggler-icon) {
+  // bslib-patched: toggler icon should follow closest navbar color mode over global mode
+  --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-dark-toggler-icon-bg)};
+}
+
 @if $enable-dark-mode {
   @include color-mode(dark) {
-    .navbar-toggler-icon {
+    // bslib-patched: toggler follows global theme unless in a light region
+    :where(.navbar:not([data-bs-theme="light"]) .navbar-toggler-icon) {
       --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-dark-toggler-icon-bg)};
     }
   }
 }
+
+.navbar[data-bs-theme="light"] {
+  // bslib-patched: Make sure local light navbar overrides page global
+  --#{$prefix}navbar-color: #{$navbar-light-color};
+  --#{$prefix}navbar-hover-color: #{$navbar-light-hover-color};
+  --#{$prefix}navbar-disabled-color: #{$navbar-light-disabled-color};
+  --#{$prefix}navbar-active-color: #{$navbar-light-active-color};
+  --#{$prefix}navbar-brand-color: #{$navbar-light-brand-color};
+  --#{$prefix}navbar-brand-hover-color: #{$navbar-light-brand-hover-color};
+  --#{$prefix}navbar-toggler-border-color: #{$navbar-light-toggler-border-color};
+
+  .navbar-toggler-icon {
+    // bslib-patched: Make sure toggler icon follows local light mode, too
+    --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-light-toggler-icon-bg)};
+  }
+}
diff --git a/tools/patches/034-bs5-navbar-bg.patch b/tools/patches/034-bs5-navbar-bg.patch
new file mode 100644
index 000000000..d8a57b5ca
--- /dev/null
+++ b/tools/patches/034-bs5-navbar-bg.patch
@@ -0,0 +1,66 @@
+diff --git a/inst/lib/bs5/scss/_navbar.scss b/inst/lib/bs5/scss/_navbar.scss
+index 988bbe09..ec497278 100644
+--- a/inst/lib/bs5/scss/_navbar.scss
++++ b/inst/lib/bs5/scss/_navbar.scss
+@@ -3,7 +3,8 @@
+ // Provide a static navbar from which we expand to create full-width, fixed, and
+ // other navbar variations.
+ 
+-.navbar {
++.navbar,
++:where([data-bs-theme="light"]) .navbar { // bslib-patched: explicitly set navbar props in light mode regions
+   // scss-docs-start navbar-css-vars
+   --#{$prefix}navbar-padding-x: #{if($navbar-padding-x == null, 0, $navbar-padding-x)};
+   --#{$prefix}navbar-padding-y: #{$navbar-padding-y};
+@@ -26,7 +27,9 @@
+   --#{$prefix}navbar-toggler-focus-width: #{$navbar-toggler-focus-width};
+   --#{$prefix}navbar-toggler-transition: #{$navbar-toggler-transition};
+   // scss-docs-end navbar-css-vars
++}
+ 
++.navbar {
+   position: relative;
+   display: flex;
+   display: -webkit-flex;
+@@ -296,6 +299,7 @@
+ }
+ 
+ .navbar-dark,
++:where([data-bs-theme="dark"]) .navbar, // bslib-patched: dark mode inside dark regions
+ .navbar[data-bs-theme="dark"] {
+   // scss-docs-start navbar-dark-css-vars
+   --#{$prefix}navbar-color: #{$navbar-dark-color};
+@@ -309,10 +313,32 @@
+   // scss-docs-end navbar-dark-css-vars
+ }
+ 
++:where(.navbar[data-bs-theme="dark"] .navbar-toggler-icon) {
++  // bslib-patched: toggler icon should follow closest navbar color mode over global mode
++  --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-dark-toggler-icon-bg)};
++}
++
+ @if $enable-dark-mode {
+   @include color-mode(dark) {
+-    .navbar-toggler-icon {
++    // bslib-patched: toggler follows global theme unless in a light region
++    :where(.navbar:not([data-bs-theme="light"]) .navbar-toggler-icon) {
+       --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-dark-toggler-icon-bg)};
+     }
+   }
+ }
++
++.navbar[data-bs-theme="light"] {
++  // bslib-patched: Make sure local light navbar overrides page global
++  --#{$prefix}navbar-color: #{$navbar-light-color};
++  --#{$prefix}navbar-hover-color: #{$navbar-light-hover-color};
++  --#{$prefix}navbar-disabled-color: #{$navbar-light-disabled-color};
++  --#{$prefix}navbar-active-color: #{$navbar-light-active-color};
++  --#{$prefix}navbar-brand-color: #{$navbar-light-brand-color};
++  --#{$prefix}navbar-brand-hover-color: #{$navbar-light-brand-hover-color};
++  --#{$prefix}navbar-toggler-border-color: #{$navbar-light-toggler-border-color};
++
++  .navbar-toggler-icon {
++    // bslib-patched: Make sure toggler icon follows local light mode, too
++    --#{$prefix}navbar-toggler-icon-bg: #{escape-svg($navbar-light-toggler-icon-bg)};
++  }
++}