diff --git a/src/locale/la.js b/src/locale/la.js
index 9dca1ecb8..bcc4c6763 100644
--- a/src/locale/la.js
+++ b/src/locale/la.js
@@ -1,9 +1,25 @@
 // Latin [la]
 import dayjs from 'dayjs'
 
+const monthFormat = 'ianuarii_februarii_martii_aprilis_maii_iunii_iulii_augusti_septembris_octobris_novembris_decembris'.split('_')
+const monthStandalone = 'ianuarius_februarius_martius_aprilis_maius_iunius_iulius_augustus_september_october_november_december'.split('_')
+const MONTHS_IN_FORMAT = /(D|[CDILMVX]+)[oD.ᵒ]?(\[[^[\]]*\]|\s)+MMMM?/
+const months = (dayjsInstance, format) => {
+  if (MONTHS_IN_FORMAT.test(format)) {
+    return monthFormat[dayjsInstance.month()]
+  }
+  return monthStandalone[dayjsInstance.month()]
+}
+months.s = monthStandalone
+months.f = monthFormat
+
 /* eslint-disable */
 // src: https://stackoverflow.com/a/9083076
+// function romanise(num) {
 function romanise(num) {
+  if (isNaN(num)) {
+    return NaN
+  }
   const key = [
     '', 'C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM',
     '', 'X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC',
@@ -12,54 +28,23 @@ function romanise(num) {
   const digits = String(+num).split('')
   let roman = ''
   let i = 3
-  if (isNaN(num)) {
-    return NaN
-  }
   while (i--) {
     roman = (key[+digits.pop() + (i * 10)] || '') + roman
   }
   return Array(+digits.join('') + 1).join('M') + roman
 }
-function getMonthInGenitive(month) {
-  switch (month) {
-    case 'ianuarius':
-      return 'ianuarii'
-    case 'februarius':
-      return 'februarii'
-    case 'martius':
-      return 'martii'
-    case 'aprilis':
-      return 'aprilis'
-    case 'maius':
-      return 'maii'
-    case 'iunius':
-      return 'iunii'
-    case 'iulius':
-      return 'iulii'
-    case 'augustus':
-      return 'augusti'
-    case 'september':
-      return 'septembris'
-    case 'october':
-      return 'octobris'
-    case 'november':
-      return 'novembris'
-    case 'december':
-      return 'decembris'
-  }
-}
 /* eslint-enable */
 const locale = {
   name: 'la',
   weekdays: 'Dominica_feria secunda_feria tertia_feria quarta_feria quinta_feria sexta_Sabbato'.split('_'),
   weekdaysShort: 'Dominica_feria II_feria III_feria IV_feria V_feria VI_Sabbato'.split('_'),
   weekdaysMin: 'Dom._II_III_IV_V_VI_Sab.'.split('_'),
-  months: 'ianuarius_februarius_martius_aprilis_maius_iunius_iulius_augustus_september_october_november_december'.split('_'),
-  monthsShort: 'ian_feb_mar_apr_mai_iun_iul_aug_sep_oct_nov_dec'.split('_'),
+  months,
+  monthsShort: 'ian._feb._mar._apr._mai._iun._iul._aug._sep._oct._nov._dec'.split('_'),
   weekStart: 0,
   yearStart: 4,
   ordinal: n => [romanise(n), 'ᵒ'].join(''),
-  // The relative time variables are in Nominative case only
+  // The relative time variables are in nominative case only
   relativeTime: {
     future: 'ad %s',
     past: 'abhinc %s',
@@ -78,10 +63,10 @@ const locale = {
   formats: {
     LT: 'HH:mm',
     LTS: 'HH:mm:ss',
-    L: ['D. MM. ', romanise('YYYY')].join(''),
-    LL: ['D. ', getMonthInGenitive('MMMM'), ' ', romanise('YYYY')].join(''),
-    LLL: ['D. ', getMonthInGenitive('MMMM'), ' ', romanise('YYYY'), ' HH:mm'].join(''),
-    LLLL: ['dddd, ', 'D. ', getMonthInGenitive('MMMM'), ' ', romanise('YYYY'), ' HH:mm'].join('')
+    L: 'D. MM. YYYY',
+    LL: 'D MMMM YYYY',
+    LLL: 'D MMMM YYYY, HH:mm',
+    LLLL: 'dddd, D MMMM YYYY, HH:mm'
   }
 }
 
diff --git a/test/locale/la.test.js b/test/locale/la.test.js
new file mode 100644
index 000000000..c24f5794c
--- /dev/null
+++ b/test/locale/la.test.js
@@ -0,0 +1,90 @@
+import MockDate from 'mockdate'
+import dayjs from '../../src'
+import advancedFormat from '../../src/plugin/advancedFormat'
+import localizedFormat from '../../src/plugin/localizedFormat'
+import relativeTime from '../../src/plugin/relativeTime'
+import '../../src/locale/la'
+
+dayjs.extend(advancedFormat)
+dayjs.extend(localizedFormat)
+dayjs.extend(relativeTime)
+dayjs.locale('la')
+
+beforeEach(() => {
+  MockDate.set(new Date())
+})
+
+afterEach(() => {
+  MockDate.reset()
+})
+
+describe('Latin: Output month name:', () => {
+  const M = [
+    [1, 'ianuarius', 'ianuarii'],
+    [2, 'februarius', 'februarii'],
+    [3, 'martius', 'martii'],
+    [4, 'aprilis', 'aprilis'],
+    [5, 'maius', 'maii'],
+    [6, 'iunius', 'iunii'],
+    [7, 'iulius', 'iulii'],
+    [8, 'augustus', 'augusti'],
+    [9, 'september', 'septembris'],
+    [10, 'october', 'octobris'],
+    [11, 'november', 'novembris'],
+    [12, 'december', 'decembris']
+  ]
+
+  it('in genitive case if day of month is output', () => {
+    M.forEach((m) => {
+      const dayjsDay = dayjs(['2020-', m[0], '-01'].join('')).locale('la').format('D MMMM')
+      const expected = ['1 ', m[2]].join('')
+      expect(dayjsDay).toBe(expected)
+    })
+  })
+
+  it('otherwise output it in nominative', () => {
+    M.forEach((m) => {
+      const dayjsDay = dayjs(['2020-', m[0], '-01'].join('')).locale('la').format('MMMM')
+      const expected = m[1]
+      expect(dayjsDay).toBe(expected)
+    })
+  })
+})
+
+it('Latin: Test relative time', () => {
+  const T = [
+    [44.4, 'second', 'paucæ secundæ'], // a few seconds
+    [89.5, 'second', 'minuta'], // a minute
+    [2, 'minute', '2 minutæ'], // 2 minutes
+    [43, 'minute', '43 minutæ'], // 43 minutes
+    [45, 'minute', 'hora'], // an hour
+    [3, 'hour', '3 horæ'], // 3 hours
+    [21, 'hour', '21 horæ'], // 21 hours
+    [1, 'day', 'dies'], // a day
+    [3, 'day', '3 dies'], // 3 day
+    [25, 'day', '25 dies'], // 25 days
+    [1, 'month', 'mensis'], // a month
+    [2, 'month', '2 menses'], // 2 month
+    [10, 'month', '10 menses'], // 10 month
+    [1, 'year', 'annus'], // a year
+    [2, 'year', '2 anni'], // 2 year
+    [5, 'year', '5 anni'], // 5 year
+    [18, 'month', '2 anni'] // 2 years
+  ]
+
+  T.forEach((t) => {
+    dayjs.locale('la')
+    const dayjsDay = dayjs()
+    const dayjsCompare = dayjs().add(t[0], t[1])
+    const expectedFrom = ['abhinc ', t[2]].join('')
+    const expectedTo = ['ad ', t[2]].join('')
+    const expectedFromTrue = t[2]
+
+    expect(dayjsDay.from(dayjsCompare)).toBe(expectedFrom)
+    expect(dayjsDay.to(dayjsCompare)).toBe(expectedTo)
+    expect(dayjsDay.from(dayjsCompare, true)).toBe(expectedFromTrue)
+  })
+})
+
+// TODO: Test formats
+// TODO: Test romanisation of year (both standalone and in dates incl L, LL, LLL, LLL)